Sciencemadness Discussion Board

New to forum - Help testing boiler water

ChrisJ - 7-1-2015 at 06:22

Hi all,

New to the forum and I'm hoping to get some help with a topic I've been struggling with. That is treating and testing steam boiler water.

There are many things I don't understand such as :



1: Total alkalinity and why is it important?

2: How to accurately measure PH especially when my water is purple from using water treatment

3: Why does a PH of around 11 or higher cause foaming and other problems when boiling? It seems a PH of 11+ causes violent boiling which causes water to be pulled from the boiler rather than just steam.

4: What PH is best to minimize corrosion and rust in regards to cast iron?


My understanding right now is total alkalinity is how much the water resists change in PH. The higher the total alkalinity the less likely you are to have a drop in PH?

I've been trying to keep my PH between 9 and 10 just based on information I have found in various places.

The water treatment I am currently using which causes the water to turn violet seems to contain the following :

1: Sodium Nitrite. % by weight 44.04
2: Sodium Triphosphate % by weight 23.52
3: Sodium Metasilicate % by weight 1.34
4: Citric Acid. % by weight 3.36

What I found interesting is this treatment starts out blue but turns violet after boiling? I'd love to know what actually causes that as they claim you can adjust treatment levels by color.

The reason I chose this forum is I am hoping to understand why I am doing things rather than just what to do. I don't like doing things blindly especially when they don't make sense to me such as trying to get an accurate PH reading using tape seems near impossible especially when the water is purple.

Thank you for your time and go easy on me. I have close no knowledge when it comes to chemistry at this point and am willing to learn everything I can.




Amos - 7-1-2015 at 06:56

I can't provide answers for everything but I can try to help with at least a couple of them.

Alkalinity is the capacity of a solution to neutralize acids, so rather than a measure of the pH of the system, it is a measure of how much base there is. No matter how much you add of a particular basic compound you add, you won't be able to make the pH any higher than the cap for that compound, but you can increase the solution's capacity to neutralize acid. So yes, it is in a way the resistance to negative change in pH.

It is my general observation that basic solutions tend to boil more violently and with a lot of spitting, which can be a major problem in reducing their volume or obtaining clean steam from them. In addition, solutions of sodium metasilicate are much more viscous than ordinary water, which will also impede smooth boiling. If you were to feel the solution between your fingers, it would probably be slippery and have a somewhat difficult time drying. Finally, you may be experiencing bumping, which boiling in violent bursts rather than at an even rate, which could be caused by the solution being too concentrated with dissolved solids or a lack of surface area for bubbles to form.

I hope I was able to help some.

ChrisJ - 7-1-2015 at 07:01

Thanks for responding!

It definitely helps some and you have me curious. If sodium metasilicate has such negative effects, do you have an idea of why it's used in steam boiler water treatment?

I'm really curious why all of the things I listed are in the product.

Amos - 7-1-2015 at 07:31

Quote: Originally posted by ChrisJ  
Thanks for responding!

It definitely helps some and you have me curious. If sodium metasilicate has such negative effects, do you have an idea of why it's used in steam boiler water treatment?

I'm really curious why all of the things I listed are in the product.


Here's good old wikipedia to save the day again: http://en.wikipedia.org/wiki/Sodium_silicate#Water_treatment
You should use it for the other substances to see why they might be used.

I'm not entirely sure why a flocculant would be necessary in a boiler here, maybe it's a general water treatment product? But given the fact that the proportion of sodium silicate is fairly low, I wouldn't say that this specific compound is a major source of your problems, but I could be wrong.

ChrisJ - 7-1-2015 at 07:37

Quote: Originally posted by No Tears Only Dreams Now  
Quote: Originally posted by ChrisJ  
Thanks for responding!

It definitely helps some and you have me curious. If sodium metasilicate has such negative effects, do you have an idea of why it's used in steam boiler water treatment?

I'm really curious why all of the things I listed are in the product.


Here's good old wikipedia to save the day again: http://en.wikipedia.org/wiki/Sodium_silicate#Water_treatment
You should use it for the other substances to see why they might be used.

I'm not entirely sure why a flocculant would be necessary in a boiler here, maybe it's a general water treatment product? But given the fact that the proportion of sodium silicate is fairly low, I wouldn't say that this specific compound is a major source of your problems, but I could be wrong.


Ah, interesting.
Perhaps it's there to cause impurities in the water to sink to the bottom of the boiler to later be removed during a blowdown.

The treatment in high dosages is said to work as a good cleaner to remove scale and sediment buildup. The downside is you can't really use the boiler during this because you can't keep the water in it.

macckone - 7-1-2015 at 08:12

Sodium Nitrite is a corrosion inhibitor.
Citric acid is to remove scale.
Sodium Triphosphate is a detergent commonly used
on steel to help remove rust and is acidic.
Sodium metasilicate is used as a defloculant.

Both sodium triphosphate and sodium metasilicate
can cause foaming which is bad in a boiler system.

The blue to purple color change suggests a pH indicator.
Before boiling the calcium carbonate load of the water
will be high but it is forced out of solution by boiling.
It is one of the relatively few compounds that is
less soluble at high temperature.

Citric acid will dissolve most metal oxides and carbonates.

The sodium nitrite will also lowers oxide levels which is
important in protecting steel.

Sodium Triphosphate is an acidic form which binds with
calcium as well as iron oxide. This helps remove rust but
can cause foaming.

Sodium metasilicate is used to settle out particles in the
system which should be removed during blowout.
It can also cause foaming.

Larger systems have a treatment tank followed by
a filter before the boiler. They also have deaerators.

Things to remember in a boiler system.
Carbon Dioxide and Oxygen in the system is bad.
Too high of an alkalinity means too much dissolved
calcium carbonate.
Feed water to the boiler should be deionized or demineralized
with the later being more common.
Additionally the feedwater should be deaerated.

Most of this is difficult for a home system but normal
maintenance for a commercial system.

ChrisJ - 7-1-2015 at 08:43

Quote: Originally posted by macckone  
Sodium Nitrite is a corrosion inhibitor.
Citric acid is to remove scale.
Sodium Triphosphate is a detergent commonly used
on steel to help remove rust and is acidic.
Sodium metasilicate is used as a defloculant.

Both sodium triphosphate and sodium metasilicate
can cause foaming which is bad in a boiler system.

The blue to purple color change suggests a pH indicator.
Before boiling the calcium carbonate load of the water
will be high but it is forced out of solution by boiling.
It is one of the relatively few compounds that is
less soluble at high temperature.

Citric acid will dissolve most metal oxides and carbonates.

The sodium nitrite will also lowers oxide levels which is
important in protecting steel.

Sodium Triphosphate is an acidic form which binds with
calcium as well as iron oxide. This helps remove rust but
can cause foaming.

Sodium metasilicate is used to settle out particles in the
system which should be removed during blowout.
It can also cause foaming.

Larger systems have a treatment tank followed by
a filter before the boiler. They also have deaerators.

Things to remember in a boiler system.
Carbon Dioxide and Oxygen in the system is bad.
Too high of an alkalinity means too much dissolved
calcium carbonate.
Feed water to the boiler should be deionized or demineralized
with the later being more common.
Additionally the feedwater should be deaerated.

Most of this is difficult for a home system but normal
maintenance for a commercial system.


Wow.

Thanks for responding! And that is an impressive response.
I have not tested total alkalinity but I have tested my TDS and it's in the low 500s.

Where does the calcium carbonate come from?

The product I am using is Steamaster tablets by Rectorseal. Am I right in assuming as long as my dose is low enough that I'm not foaming, it's safe? Sunday I did some cleaning and ended up with a bit too much so I drained and added enough fresh water to get things back to normal.


Bezaleel - 7-1-2015 at 10:07

Calcium carbonate is almost always dissolved in tapwater. It simply comes from the source of the tap water. The higher the concentration, the 'harder' the water is. Concentrations are strongly dependent on the region you live in.

Note that in some regions also considerable amounts of iron hydroxide/oxide are present in tap water. This will cause the chalk residues in boiling equipment to turn brownish.

aga - 7-1-2015 at 11:20

Quote: Originally posted by ChrisJ  
Where does the calcium carbonate come from?

If you imagine rain falling in the mountains, percolating through the rocks, then joining a river somewhere before hitting the reservoir, and becoming part of your water supply piping.

The rainwater contains a tiny amount of carbon dioxide.
Carbon dioxide in water forms the weak acid Carbonic acid.

The rocks contain calcium oxide (limestone) and hydroxide due to the water.

This reacts with the carbonic acid to create calcium carbonate.

Depending on what is in the rocks that the water has passed through, you can have all sorts of stuff in your tap water - Iron, Aluminium, Crocodiles, Uranium ...

[Edited on 7-1-2015 by aga]

ChrisJ - 7-1-2015 at 13:56

Thank you all for replying!


Besides the dosage question (is it safe as long as the boiler isn't foaming?)
I'm also wondering if Sodium Metasilicate in the treatment product helps remove oil from the water which typically floats on top?

I added some new piping in the fall and just got around to skimming the boiler last weekend and it didn't seem like any oil was in it. Would Sodium Metasilicate have mixed with the oil and caused it to fall to the bottom where it would've been removed during a blowdown? Normally oil will float on the water forever or until you skim from the top.


Seemed really odd to me unless there was far less oil in the new pipes and fittings than I thought.

[Edited on 1-7-2015 by ChrisJ]

[Edited on 1-7-2015 by ChrisJ]

aga - 7-1-2015 at 15:11

Fatty stuff will always float on water, if it is less dense.

Stuff that falls out of the water as a solid is called a Precipitate.

If you have a mix of stuff in water that forms a precipitate, then something(s) reacted to create new chemical structures.

Exceptions are things like very fine particles suspended in the water, which normally remain suspended in the water due to their very low weight.

A Flocculant, such as Sodium Metasilicate, basically makes those particles stick together, making the combined mass big enough to make it fall out of the water.

ChrisJ - 7-1-2015 at 16:31

Quote: Originally posted by aga  
Fatty stuff will always float on water, if it is less dense.

Stuff that falls out of the water as a solid is called a Precipitate.

If you have a mix of stuff in water that forms a precipitate, then something(s) reacted to create new chemical structures.

Exceptions are things like very fine particles suspended in the water, which normally remain suspended in the water due to their very low weight.

A Flocculant, such as Sodium Metasilicate, basically makes those particles stick together, making the combined mass big enough to make it fall out of the water.


Ah ok. So oil stays on top.

macckone - 7-1-2015 at 17:17

Maybe, oil by itself will float but when combined in particles with sodium metasilicate and sodium triphosphate it could be sequestered and sink or even be taken into solution.
Flocculants don't necessarily change things chemically to work.

Amos - 7-1-2015 at 18:49

I'd like to caution the notion that calcium carbonate is the factor causing the alkalinity; ChrisJ mentioned that the pH was 11, which is far too high for calcium carbonate to be causing it(pH 9), especially given that it is virtually insoluble in the first place. Solutions of sodium metasilicate are always basic unless acidified, so it could be a contributing factor.

Citric acid will not be performing as an acid in these highly basic conditions, rather it will be present as various dissolved citrate salts, which may precipitate insoluble citrate complexes? No idea.

And aga, if limestone was composed of calcium oxide, your skin might start to bubble when you touch it. Limestone is calcium CARBONATe, generally.

ChrisJ - 7-1-2015 at 19:00

Quote: Originally posted by No Tears Only Dreams Now  
I'd like to caution the notion that calcium carbonate is the factor causing the alkalinity; ChrisJ mentioned that the pH was 11, which is far too high for calcium carbonate to be causing it(pH 9), especially given that it is virtually insoluble in the first place. Solutions of sodium metasilicate are always basic unless acidified, so it could be a contributing factor.

Citric acid will not be performing as an acid in these highly basic conditions, rather it will be present as various dissolved citrate salts, which may precipitate insoluble citrate complexes? No idea.

And aga, if limestone was composed of calcium oxide, your skin might start to bubble when you touch it. Limestone is calcium CARBONATe, generally.


I don't know what my ph was when the boiler was priming (water being pulled into mains).

I know right now it's between 9 and 10 and things are happy. But, it also sounds like the chemicals alone could cause foaming issues, ph aside.

Measuring ph is something else I think I need to improve on. I'm using these and am planning on switching to a much coarser version that does from 6 to 11.

This is what I've been using.
https://www.microessentiallab.com/ProductInfo/F03-WIDRG-0001...

This is what I ordered as it seemed to be much better for my uses
https://www.microessentiallab.com/ProductInfo/F01-WIDRG-0601...

Minor issue is I contacted their tech support and was told neither of these are intended for testing water and that I should use one of their water testing kits. Thing is, neither water testing kit they offer does the range I want.

How could these general purpose strips that say they can be used for many things, not be for water!?

ChrisJ - 7-1-2015 at 19:05

Here are two videos showing the difference between a good amount of treatment, and when I had too much.

Surprisingly there were no other symptoms at the time so I guess I didn't go too far, but enough to raise the pressure quite a bit.


Normal conditions
http://youtu.be/ssTosd_UiWY


Too much water treatment
http://youtu.be/NAtcDLePJis

Surprising to me, even with too much treatment my water line stayed very stable. I'm guessing if I added more, this would have changed fast.
http://youtu.be/dPIx0xnEVUo

The steam was from a bucket of hot water I had drained from the boiler that was directly under the camera.

[Edited on 1-8-2015 by ChrisJ]

macckone - 7-1-2015 at 22:21

Alkalinity is not the same as pH.
Alkalinity is a measure of ions in solution that will react with acid to neutralize it.
pH is the actual amount of H+ ions in solution.
Based on the information provided the alkalinity is probably ok as is the pH.
Citrates are generally soluble salts.

ChrisJ - 8-1-2015 at 06:35

Quote: Originally posted by macckone  
Alkalinity is not the same as pH.
Alkalinity is a measure of ions in solution that will react with acid to neutralize it.
pH is the actual amount of H+ ions in solution.
Based on the information provided the alkalinity is probably ok as is the pH.
Citrates are generally soluble salts.


Ah,

You just gave me exactly what I needed to find useful information on PH vs total alkalinity. Just searching for either usually brings up pool websites and is useless.

I finally get it.



feacetech - 8-1-2015 at 14:55

measure P2 alaklinity by adding BaCl (in excess) and phenolphthalein and titrating (this will tell you how much caustic you have in the boiler).

Three types of alaklinity P1 P2 and total.

Not sure why the high pH is causing carry over, if fat is getting back through with the condensate this can cause foaming and carry over if not total boiler shut down to due to high and low level alarms from soap formation. Your chemicals seem odd and I guess is they are an easy one step treament that wont fit all applications.

How are you dosing the boiler dose pot or pumps?

Measure your condensate return if you have any (tds, turbity).

Meaure the TDS (condcutivity) of the boiler and the feed then you can estimate cycles.

Also measure phosphate levels (since you are using a phosphate treatment). Too much can be just as bad as none.

You are using a sulfite as an oxygen scavenger you can get test strips that measure sulfite levels(like pH paper (Merk make them) the pink colour of your water might be a problem they go pink the more sulfite you add).

Are you pretreating the the feed water (softner or demin)?

Are you preheating the water before it goes into the boiler to help drive off oxygen.

Qulaity of your raw water will determine the best treatment, measure total harndess, TDS, pH, silica.

Then if you run a pretreatment measure your feed water conductivity, hardness and silica.

By the look if it you are runnign a phosphate programe so you probably have little in the way of pretreatment. You are trying to do a couple of things in the boiler.

Remove the carbonate (to prevent scale build up on hot surfaces) as a mobile serpentine phosphate sludge and thus blow it out of the boiler via bottom blowdown.

You are trying to remove all dissolved oxygen to prevent corrosion having a sulfite reserve in the boiler would mean that all oxygen is scavenged.

You are keeping the pH high to avoid silica scale and also encourage the formation of magnitite in the boiler to help prevent corrosion (silica scale is by far the worse type of scale very hard to remove). If silca is very high it can carry over (bad block heat exchangers etc).

TDS and cycles is key to running a good boiler (15-20 cycles). The lower the better if you have a dirty scaly boiler.

Sodium lignosulfonate is good for dirty boilers.

Sodium erythorbate is good for metal passivation and oxygen scavenging in conjunction with a sulfite.

Are you worried about condensate corrosion and can you add a volatile/filming amine? Not if its a food application.

I could be wrong, and you are using high quality feed water and are running a chelation programe(The cirtic acid!)?

What sort of boiler is it, fire tube or water tube?

Carbonate has retrograde solubility (is less soluable in hot water) so it sticks to the hot surfaces of your boiler, plus it is a good insulator so you loss efficency in your boiler, also it can cause under deposit corrison, worse case is your firetube may warp if its a firetube boiler (metal gets very hot because its insulated by concrete).

To much caustic can cause caustic embrittlement of the metal over time.

I would be very carfull about using citric acid in your boiler, over use will eat your boiler up plus remove any good coatings you have formed.


If you have no pre treamnet and a typical raw water (~100 tds, some carbonate hardness, not much silica, low cholride, normal pH 6-8)

I would get a water softner and run a phosphate programe just in case you get slipage or your softner fails.

Phosphate additive, caustic and a sludge modifier. Plus a sulfite and a vitamin c analouge in the feed. (the more preheat the less sulfite you will need). Alkaline tanins can work if its not food related in application.

run a sulfite reserve of 10-30ppm.
P2 alk of 300-600ppm.
Phosphate depends on the additive about 20-50ppm depedning on the type.
pH 10.5-12, I think 11.2 is the magic number.
20 cycles max, by the sound of it your boiler doesnt work hard and has low cycles anyway? (unless you have good feed water low tds).

[Edited on 8-1-2015 by feacetech]

aga - 8-1-2015 at 15:26

I don't know if more pH explanation will help (or if my understanding is totally correct) but here goes anyway ...

When an atom or molecule loses or gains an electron, it gains or loses a Charge of 1, and is called an Ion.
(some can lose or gain more than 1)

Hydrogen has only 1 proton and 1 electron, so if it loses it's electron, it has an overall Positive charge of +1

pH is a measure of the Concentration of those positively charged electron-deficient Hydrogen Ions (H+) in the stuff you're interested in.

Fairly recently it has been discovered that H+ doesn't really exist, it's H3O+ in reality, but the pH scale was worked out before that discovery.

pH is defined as the Negative log of the Concentration of the H+ ions.

Concentration is a strange one : it's measured as how many molecules/atoms there are in 1 Litre, and the 'how many' is measured as how many Advogadro Contant molecules/atoms there are in a litre, rather than a simple count (!).

So that's the actual number of molecules/atoms divided by 6.022 * 10^23 there are in a Litre, also called the Molar Concentration, normally stated as [M].

It sounds odd, yet it makes more sense than dealing with Vast numbers of particles.

e.g. The Mass of 6.022 * 10^23 bits of an Element is what you find as it's mass on the periodic table.

ChrisJ - 8-1-2015 at 16:13

Quote: Originally posted by feacetech  
measure P2 alaklinity by adding BaCl (in excess) and phenolphthalein and titrating (this will tell you how much caustic you have in the boiler).

Three types of alaklinity P1 P2 and total.

Not sure why the high pH is causing carry over, if fat is getting back through with the condensate this can cause foaming and carry over if not total boiler shut down to due to high and low level alarms from soap formation. Your chemicals seem odd and I guess is they are an easy one step treament that wont fit all applications.

How are you dosing the boiler dose pot or pumps?

Measure your condensate return if you have any (tds, turbity).

Meaure the TDS (condcutivity) of the boiler and the feed then you can estimate cycles.

Also measure phosphate levels (since you are using a phosphate treatment). Too much can be just as bad as none.

You are using a sulfite as an oxygen scavenger you can get test strips that measure sulfite levels(like pH paper (Merk make them) the pink colour of your water might be a problem they go pink the more sulfite you add).

Are you pretreating the the feed water (softner or demin)?

Are you preheating the water before it goes into the boiler to help drive off oxygen.

Qulaity of your raw water will determine the best treatment, measure total harndess, TDS, pH, silica.

Then if you run a pretreatment measure your feed water conductivity, hardness and silica.

By the look if it you are runnign a phosphate programe so you probably have little in the way of pretreatment. You are trying to do a couple of things in the boiler.

Remove the carbonate (to prevent scale build up on hot surfaces) as a mobile serpentine phosphate sludge and thus blow it out of the boiler via bottom blowdown.

You are trying to remove all dissolved oxygen to prevent corrosion having a sulfite reserve in the boiler would mean that all oxygen is scavenged.

You are keeping the pH high to avoid silica scale and also encourage the formation of magnitite in the boiler to help prevent corrosion (silica scale is by far the worse type of scale very hard to remove). If silca is very high it can carry over (bad block heat exchangers etc).

TDS and cycles is key to running a good boiler (15-20 cycles). The lower the better if you have a dirty scaly boiler.

Sodium lignosulfonate is good for dirty boilers.

Sodium erythorbate is good for metal passivation and oxygen scavenging in conjunction with a sulfite.

Are you worried about condensate corrosion and can you add a volatile/filming amine? Not if its a food application.

I could be wrong, and you are using high quality feed water and are running a chelation programe(The cirtic acid!)?

What sort of boiler is it, fire tube or water tube?

Carbonate has retrograde solubility (is less soluable in hot water) so it sticks to the hot surfaces of your boiler, plus it is a good insulator so you loss efficency in your boiler, also it can cause under deposit corrison, worse case is your firetube may warp if its a firetube boiler (metal gets very hot because its insulated by concrete).

To much caustic can cause caustic embrittlement of the metal over time.

I would be very carfull about using citric acid in your boiler, over use will eat your boiler up plus remove any good coatings you have formed.


If you have no pre treamnet and a typical raw water (~100 tds, some carbonate hardness, not much silica, low cholride, normal pH 6-8)

I would get a water softner and run a phosphate programe just in case you get slipage or your softner fails.

Phosphate additive, caustic and a sludge modifier. Plus a sulfite and a vitamin c analouge in the feed. (the more preheat the less sulfite you will need). Alkaline tanins can work if its not food related in application.

run a sulfite reserve of 10-30ppm.
P2 alk of 300-600ppm.
Phosphate depends on the additive about 20-50ppm depedning on the type.
pH 10.5-12, I think 11.2 is the magic number.
20 cycles max, by the sound of it your boiler doesnt work hard and has low cycles anyway? (unless you have good feed water low tds).

[Edited on 8-1-2015 by feacetech]



Wow, feacetech you just went so far over my head I can't even see you. :)

This is a home heating steam boiler. It's not a tube boiler but rather what I believe is called a pin type where it's just a cast iron block with passages through the water lined with stubs.

I just happen to be very anal and learned very fast that raw water wasn't a good idea. I use around 1/2 gallon of water per month and do not have an autofeeder. I manually feed while the burner is firing and when I know it will boil the fresh water for a while. The high PH causing foaming was an assumption I had made based on what I had been told in the past but this could easily be false. That's why I'm here, to learn the right way to do things and understand why I'm doing them. I'd like to talk more if possible? Is there another way to contact you?

I've attached two pictures of the boiler from when I was installing it back in 2011.

More pictures of the project can be found at this URL
https://picasaweb.google.com/thetube0a3/Boiler?authkey=Gv1sR...

boilerfinal.jpg - 90kB done1.jpg - 144kB

[Edited on 1-9-2015 by ChrisJ]

[Edited on 1-9-2015 by ChrisJ]

aga - 8-1-2015 at 16:33

Quote:
I'd like to talk more if possible?

Keep it Public and open : we all learn more that way !

ChrisJ - 8-1-2015 at 16:35

Quote: Originally posted by aga  
Quote:
I'd like to talk more if possible?

Keep it Public and open : we all learn more that way !


Oh, alright. :)

By the way, thank you for your PH explanation. It was helpful.

feacetech - 8-1-2015 at 18:51

So you add make up water manually? If so losses must be really low?

You could fill with DI water (deionised water you can get filters that do this TDS should be close to zero), boil b4 you put it in to de-aerate it, add some tablets at required dose and you should be all good. Check you TDS before you put it in (if you have a conductivity meter then you can estimate cycles). the only real way to get stuff out of the system is from blow down if you have no losses. Steam losses will increase your TDS (total dissolved solids) and therefore your treatment chemicals and unwanted dissolved ions. If its closed loop it shouldn't need much blow down or make up.

That we tap on the side looks like a blow down or is it a sample port (or both lol)? Does it have automatic blow down, manual bottom blow down or none apart from sample port/manual side blowdown?

I was picturing a larger fire tube boiler for a large scale home brew operation or an industrial boiler you wanted to find out more about :p.

Just to be sure is it a steam generator or a pressurised hot water boiler? this is important to determine what sort of treatment you want.

Not sure what's on the consumer market for these sort of things, but your choice should be dependent on your feed water quality. The better the quality the more fancy treatment you can try and succeed with and have nice efficient long lasting boiler (like your tablets).

An option if its a closed loop hot water boiler on low quality feed is to find a cheap industrial treatment with Alk and tannins and some phosphate and you should be good. Tannin is cheap and long lasting and good for some one who doesn't want too much effort.

Phosphates/phosphonates form a sludge with the Ca and Mg hardness and higher alkalinity encourages the formation of magnetite among other things. Tannins as a long lasting oxygen scavenger.

There's a test for tannins it involves some KMnO4 tablets and is very easy. You can get phosphate test strips and sulphite test strips as well.

Catalysed sulphite is very fast at oxygen scavenging and good.

Tannins and slower but hold a reserve for longer.

Having the system turn off and cool down is also the enemy as it can create a vacuum that sucks in unwanted atmosphere that dissolves in the water once the system cools down and consumes oxygen scavengers. Gasses are more soluble in cold water as a rule of thumb.

What is the trade name of the tablets and what are the recommended parameters for the treatment?

Since its small and probably delicate you want to go for the highest quality feed water with the best treatment IMHO.

It should be spotless on the inside and a nice gunmetal grey if done right.

Also when I was talking cycles I meant cycles of concentration basically how much more times concentrated your bolier water is vs feed water. You can estimate this by (TDS of system)/(TDS of Feed water). Low TDS treatment is more advanced than hard water treatment.

If it is in fact a steam boiler for best results you want to have a mildly alkaline low TDS treatment and make up with high quality feed water (very low TDS).

Think of it like this if you have high grade feed water you just have to worry about minute impurities (Chelation) and concentrate on corrosion (oxygen-scavenger and pre heating if you don't what to waste chemicals) and metal passivation instead.

[Edited on 9-1-2015 by feacetech]

ChrisJ - 8-1-2015 at 19:28

Quote: Originally posted by feacetech  
So you add make up water manually? If so losses must be really low?

You could fill with DI water (deionised water you can get filters that do this TDS should be close to zero), boil b4 you put it in to de-aerate it, add some tablets at required dose and you should be all good. Check you TDS before you put it in (if you have a conductivity meter then you can estimate cycles). the only real way to get stuff out of the system is from blow down if you have no losses. Steam losses will increase your TDS (total dissolved solids) and therefore your treatment chemicals and unwanted dissolved ions. If its closed loop it shouldn't need much blow down or make up.

That we tap on the side looks like a blow down or is it a sample port (or both lol)? Does it have automatic blow down, manual bottom blow down or none apart from sample port/manual side blowdown?

I was picturing a larger fir tube boiler for a large scale home brew:p.

Is it a steam generator or a hot water boiler? this is important to determine what sort of treatment you want.

Not sure what's on the consumer market for these sort of things, but your choice should be dependent on your feed water quality. The better the quality the more fancy treatment you can try and succeed with and have nice efficient long lasting boiler (like your tablets).

If its a closed loop hot water boiler find a cheap industrial treatment with Alk and tannins and some phosphate and you should be good. Tannin is cheap and long lasting and good for some one who doesn't want too much effort.

There's a test for tannins it involves some KMnO4 tablets and is very easy.

Catalysed sulphite is very fast at oxygen scavenging and good.


What are the tablets and what are the recommended parameters for the treatment?

You can get phosphate test strips and sulphite test strips as well

Since its small and probably delicate you want to go for the highest quality feed water with the best treatment IMHO.

It should be spotless on the inside and a nice gunmetal grey if done right.

Also when I was talking cycles I meant cycles of concentration basically how much more times concentrated you water is vs feed. You can estimate this by (TDS of system)/(TDS of Feed water).

If it is in fact a steam boiler for best results you want to have a low TDS treatment and make up with high quality feed water (very low TDS).

Think of it like this if you have high grade feed water you just have to worry about minute impurities (Chelation) and concentrate on corrosion (oxygen-scavenger and pre heating if you don't what to waste chemicals) and metal passivation instead.

[Edited on 9-1-2015 by feacetech]


I try to keep my losses to a minimum, typically 1/2 gallon of water per month if it's fairly cold out.

This is a steam boiler and my feed water is city water with a typical PH of 7 and TDS is usually around 250 ppm if memory serves. I just checked the boiler's TDS on the weekend and had 512.

The tap on the side is known by the manufacturer as "the boiler drain". Sadly, home heating boilers like this don't get much attention from their owners and most don't even know what a blow down is. :( They also often rely on autofeeders which almost always add water right before the boiler shuts down and most don't even keep track of how much is added.

We bought this house in 2011 and the previous owner rotted two boilers out in 8 years due to leaks and low PH. From the short time I saw the leaking boiler work I'd say it was taking in a gallon or more of fresh water per day and no one cared because an autofeeder was doing it.

My return water has a TDS of between 1 and 2 ppm which I understand means the steam I am producing is very dry vs the boiler's 500+ ppm.

Before I started using treatment when I measured the boiler water's PH I found it was around a low 6. I found this surprising as my tap water is pretty much always a 7. My understanding is this takes place due to the water absorbing carbonic acid after condensing in the radiators and trickling back through the system? Again, this is what I had heard from someone 3 years ago so I could be wrong, just like the high PH causing foaming.

Now, as far as the pills I am using they are Rectorseal Steamaster tablets. The problem is, I think their instructions assume a far larger boiler because they want me to use 12 pills based solely on my boiler's output. The issue is, my system only holds 10 gallons of water and even 3 pills causes foaming and carryover. I know quite a few people using these pills and not one of them can go past 2 pills in a home heating system. In fact many can't use over 1 pill.

You're right, these boilers do seem fairly delicate. Sadly, many rott out in 5-10 years due to abuse. No water treatment, no blowdowns, access makeup water added constantly due to leaks etc.

Almost always they rott out just above the water line.

What I can say for the Steamaster tablets is the difference between them and plain water in my system is night and day. Before them my water was always rusty, anytime I drained water it was dark brown, nasty and rusty. I started using the tablets in 2012 and ever since I never see rust in the gauge glass and when I do a blow down after several months there's practically no rust.

I've attached a picture from 2012 showing what my gauge glass used to look like for the first year I ran the boiler. After using treatment that glass stays practically spotless. After an entire season it will get a slight rust cloud on it, but nothing like before. I try to keep the PH between 9 and 10 but have had a hard time reading the Phydrion tape I have because 9 10 and 11 look almost the same. The purple color isn't helping either.

I do expect some rust as the entire system is open to the atmosphere. Everytime I produce steam it pushes air out of the system and then afterwards more air gets sucked in. That combined with steel piping, cast iron fittings and cast iron radiators means rust. I've also heard distilled water attacks metal more than normal tap water? If that's the case it's surprising how long cast iron radiators last.

My system typically runs at around 1"WC and I try to keep the pressure as low as possible by venting fast. Most systems like this unfortunately run as high as 2 PSI due to slow venting and grossly oversized boilers.
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[Edited on 1-9-2015 by ChrisJ]

[Edited on 1-9-2015 by ChrisJ]

[Edited on 1-9-2015 by ChrisJ]

feacetech - 8-1-2015 at 19:49

so basically your condensate return is very similar to distilled water + little bits of your pipes and heat exchangers from that pesky CO2. Hence the low TDS means high purity.

Test the pH of your condensate return to get and idea of how corrosive it is.

The steam is pure and then condenses and returns to the system.

High purity water can be more corrosive to metals below the water line. hence the treatment is more advanced requires gentle pH correction, metal passivation, chelation(to remove unwanted metals ions among other things) and oxygen control.

It sounds more like oxygen attack from the description of the tide line corrosion.

You should also find a liquid or tablet that treats your steam side it will be volatile and travel with your steam condensing out at different stages neutralising the carbonic acid and passivating your metal.

something like this from a quick look (there might be a better home option somewhere)
http://www.accepta.com/water-treatment-chemicals-wastewater-...

When you shut down you should find a treatment for this as well like a slug dose of oxygen scavenger.

plug the leaks and close of the pressure relief when its shut down for the summer.

you could also put an injection fitting in the steam line and dose some treatment in that way like vitamin c analogues and a mild pH adjustment.

This link may be helpful when learning about water treatment of boilers.

http://www.gewater.com/handbook/boiler_water_systems/ch_11_p...

Your tablets appear to be self indicating so once the system is violet you have enough.

once you have steady state of chemical in the boiler add enough tablet to make up then add the water

boil the water before for 10-15mins add the right amount of treatment and dose the boiler

it looks like you can clean your boiler (hence the citric acid mild acid good and dissolving iron oxide and scale) with the tablets as well.

get some a sulphite test kit to see how good the tablets are might be hard considering the violet colour you water will take on.

If you can find a better home treatment to use in conjunction high quality feed water (DI, softened) would be good it wont have as much phosphate in it as it wont need it to react with the hardness

it can be bad to use hard water treatment on good feed water and vice versa

Over dosing with old technology phosphates can cause foaming.

[Edited on 9-1-2015 by feacetech]

ChrisJ - 8-1-2015 at 19:54

Here are the instructions to the Steamaster tablets.

What's confusing is they say to add four tablets per 100sqft of radiation (I have 392sqft) OR until the water turns violet. They are recommending I use 16 tablets and yet 1 turns the water a light violet color, 2 turns it a darker violet color.

This is why I'm so curious about the color. What is it and how does it work? Adding more only seems to make it darker.

The pills themselves are blue and stay blue even in water. It's either not until it gets hot, or until it dissolves into the water that the color changes.

Capture.JPG - 158kB

[Edited on 1-9-2015 by ChrisJ]

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feacetech - 8-1-2015 at 20:05

I was just editing my post if you want to reread. By the sound of it go by colour as it appears to be designed for higher output boilers.

when you shut her down for summer slug dose her. Or drain her and pressurise with an inherit gas if you want to be nerdy.

halfway through he winter follow the slug dose cleaning treatment if you are worried about build up.

over dosing can actuality eat your boiler since it contains citric acid as well. nowhere near as much as oxygen though.

Im not sure how the indicator works but it my not be linked to the sulphite which you want to use for oxygen scavenging. Then again it may be. If the boiler water loses the violet colour you may have to add a little more over time.

this may be a better product they also have one with anti foam surgex
http://www.rectorseal.com/index.php/8-way/

they are not very forthcoming with design of treatment in there PDS i.e. hard, soft or di water


these guys sell home boiler treatment but its looks large scale and expensive you might end up with 2 lifetimes worth of chemical. Its Hard to find residential boiler treatment products.

http://diyboilertreatment.com/shoppingcart/index.php?main_pa...


[Edited on 9-1-2015 by feacetech]

ChrisJ - 8-1-2015 at 20:28

Quote: Originally posted by feacetech  
I was just editing my post if you want to reread. By the sound of it go by colour as it appears to be designed for higher output boilers.

when you shut her down for summer slug dose her. Or drain her and pressurise with an inherit gas if you want to be nerdy.

halfway through he winter follow the slug dose cleaning treatment if you are worried about build up.

over dosing can actuality eat your boiler since it contains citric acid as well. nowhere near as much as oxygen though.

Im not sure how the indicator works but it my not be linked to the sulphite which you want to use for oxygen scavenging. Then again it may be. If the boiler water loses the violet colour you may have to add a little more over time.

this may be a better product they also have one with anti foam surgex
http://www.rectorseal.com/index.php/8-way/

they are not very forthcoming with design of treatment in there PDS i.e. hard, soft or di water

[Edited on 9-1-2015 by feacetech]

[Edited on 9-1-2015 by feacetech]


I went back and re-read, thanks!

I just emailed them and I'm hoping for a response this time. All I'm asking them for is how to know when I'm using the proper dose. The thing that confuses me is all I ever get is light purple, purple, or purpler but what's correct?

You mentioned using a slug dose during the winter for cleaning, and then again for summer storage. But then said too much can eat the metal so I'm a bit confused by that in regards to summer shutdown. How much is too much at that point?



Again, thank you for such thorough responses. I really appreciate it.





[Edited on 1-9-2015 by ChrisJ]

feacetech - 8-1-2015 at 20:31

as in under pressure and hot, having an overdose for a long time can eat metal

it wont be so bad when its shut down for summer?

do you drain it for summer? that might be just as good with a little system. as long as you get it nice and dry.

I was just reading the guide the clean is for a short time 3hours.

Try and find a steam treatment or combo water and steam treatment if you are getting corrosion in your steam pipes and valves. Or a non foaming formula if you cant get the right dose, I guess they are design for normal hard water since they have PO4 in them?

The TDS of your condensate does look good but it may vary during operation i.e. if its been cold the initial slug might be acidic and full of rust. From CO2 dissolving in the film of water in you steam system.


[Edited on 9-1-2015 by feacetech]

[Edited on 9-1-2015 by feacetech]

aga - 9-1-2015 at 10:59

Assuming that the Colour is a pH indicator of some kind, grind up a bit of a tablet and dissolve it in water.

Add a small amount of vinegar (= an acid) and see if it changes colour.

Then add some ammonia (=a base) and see if it changes back.

For the Nerdy Air Purge, use an old 5 gallon bottle, a bit of pipe, vinegar & sodium bicarbonate to make a Carbon Dioxide generator.

Remember that humans can't live in a CO2 atmosphere, so take care !

ChrisJ - 9-1-2015 at 11:53

Quote: Originally posted by aga  
Assuming that the Colour is a pH indicator of some kind, grind up a bit of a tablet and dissolve it in water.

Add a small amount of vinegar (= an acid) and see if it changes colour.

Then add some ammonia (=a base) and see if it changes back.

For the Nerdy Air Purge, use an old 5 gallon bottle, a bit of pipe, vinegar & sodium bicarbonate to make a Carbon Dioxide generator.

Remember that humans can't live in a CO2 atmosphere, so take care !


I'm assuming I could add small amounts to a pot of boiling water until it's violet and then add some vinegar to see if it changes and if so, add more of a tablet to see if I can bring it back to violet?


feacetech - 9-1-2015 at 13:30

it could also be linked to a phosphate or sulphite

If its linked to pH there's a good chance that your sulphite levels could drop off over time

Do you have a sulphite test kit/ strips


ChrisJ - 9-1-2015 at 13:55

Quote: Originally posted by feacetech  
it could also be linked to a phosphate or sulphite

If its linked to pH there's a good chance that your sulphite levels could drop off over time

Do you have a sulphite test kit/ strips



Not yet.
Sounds like I should though?

aga - 9-1-2015 at 14:33

Quote: Originally posted by ChrisJ  
I'm assuming I could add small amounts to a pot of boiling water until it's violet and then add some vinegar to see if it changes and if so, add more of a tablet to see if I can bring it back to violet?

Welcome to Chemistry !

Just Experiment with it in small (e.g. 5 g) amounts.

Measure and write down stuff like weight of tablet, temperature of water, how much vinegar, what % it says on the vinegar bottle, and what you see happen, and when.

Personally i'd start with cold water (room temperature), records the results, then do it all exactly the same way, but with boiling water.

Amazingly enough, that kind of data can be calculated back into an insight into what is actually happening at a chemical level.

Edit:

You will get more mileage using an acid and a base : i.e. vinegar or ammonia.

The 'depth' of the colour isn't as important as the Change in colour from state 1 (nothing added) to state 2 (acid or base added).

An excellent pH indicator for beginners is Red Cabbage juice.
Whizz up some red cabbage, add hot water, wait 10 mins, strain out the purple juice.

Add a few drops to a Base (opposite of an acid) and it goes green.
Do the same to an Acid and it goes pink.

Fresh red cabbage juice goes about 8 different colours depending on pH, and the individual's colour perception.

[Edited on 9-1-2015 by aga]

feacetech - 9-1-2015 at 15:16

One other thing

does your sight glass have a blow down

you can use that to blow down floating solids since it takes water from higher in the boiler

its important to blow down sight glasses (on larger boilers) as they can become blocked.


shut glass steam valve blow out with bottom valve open

shut bottom blow out with steam open

repeat 2 or three times

it may not have a blow down on the glass as I cant see a third valve

In industrial boilers over time the gage glass can become thin down the bottom from the hot caustic water :o

Also you might like this
https://www.youtube.com/watch?v=PsSVfAg1kRg

larger fire tube boiler failure at a school

[Edited on 9-1-2015 by feacetech]

ChrisJ - 9-1-2015 at 16:15

Quote: Originally posted by feacetech  
One other thing

does your sight glass have a blow down

you can use that to blow down floating solids since it takes water from higher in the boiler

its important to blow down sight glasses (on larger boilers) as they can become blocked.


shut glass steam valve blow out with bottom valve open

shut bottom blow out with steam open

repeat 2 or three times

it may not have a blow down on the glass as I cant see a third valve

In industrial boilers over time the gage glass can become thin down the bottom from the hot caustic water :o

Also you might like this
https://www.youtube.com/watch?v=PsSVfAg1kRg

larger fire tube boiler failure at a school

[Edited on 9-1-2015 by feacetech]


The gauge glass used to have a tiny drain you opened using a wrench. I replaced it with a 1/4 turn ball valve.

Also, I have a skim port to remove stuff floating on the surface. The skimmer is the 1 1/2" port with a plug in. I used a brass coupler and brass plug to ensure I could always get it apart easily.




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feacetech - 9-1-2015 at 16:58

That looks nice, seems like your doing a good job.

I guessing with that valve arrangement you cant do what I said to the sight glass as when you shut the bottom valve you cant purge it with the steam side?

I would get a sulphite test kit to make sure u keep a sulphite reserve. buy some sulphite or catalysed sulphite extra on the side, if your reserves drop.

Read about Hydrazine if you can get your hands on some. it has some bad properties but if handled carefully it might make a nice boiler :o.

Normal sulphite I think should be >30 ppm (mg/L) but not too much or its a waste

catalysed sulphite 10-30 ppm

Boil your water for some time before you use it as make up, so you don't add unneeded dissolved gasses. Add just the right amount of treatment and make up with that.

Find a volatile steam treatment you can add
and keep an eye on condensate returns pH and TDS

You shouldn't need to DI or soften your water if that treatment is for hard water, good feed water and better treatments are superior however.

Where do you work, does your employer have a larger boiler with chemical treatment, make friends with the boiler man. See what they are doing. If its a decent size I'm sure they could spare a few mils of treatment. You could also look at their test record and see what treatment programme they are running.

Get a log book keep track of stuff

How much water you add(If you don't do any blow down, constantly add water, and know your system volume you can use this to figure out your cycles etc) , tests of water (ideally pH, TDS, sulphite, p2 alk, PO4), condensate (pH, TDS if you worried about steam side corrosion) and when you have flushed and cleaned the system etc. The logs will give you an idea of how long your sulphite is lasting etc. The trouble with an all in one is just what you notice your sulphite is low, every thing else might be still in the sweet spot so you add more and get every thing too concentrated and it starts to foam and carry over small amounts of boiler water or worse. With your Product query ask them what the ideal parameters are for your feed water (soft/hard) max impurities. Ideal boiler water PO4 levels, pH etc.

My guess with a small boiler like that is you wouldn't even need to blow down as annual draining and cleaning should be enough. Do a good job of cleaning, the sludge in the bottom can set like concrete if left to dry.

On/off seasonal operation isn't great for boilers but that's just the way it is.

Judging by the colour it looks like your tablets a pH indicator http://en.wikipedia.org/wiki/Phenolphthalein

If you add Acid (vinegar, sprits of salt, or H2SO4 drain cleaner) it should go from pink to colourless if its Phenolphthalein.

[Edited on 10-1-2015 by feacetech]

ChrisJ - 9-1-2015 at 17:06

Quote: Originally posted by feacetech  
That looks nice, seems like your doing a good job.

I guessing with that valve arrangement you cant do what I said to the sight glass as when you shut the bottom valve you cant purge it with the steam side?

I would get a sulphite test kit to make sure u keep a sulphite reserve. buy some sulphite or catalysed sulphite extra on the side, if your reserves drop.

Read about Hydrazine if you can get your hands on some. it has some bad properties but if handled carefully it might make a nice boiler :o.

Normal sulphite I think should be >30 ppm (mg/L) but not too much or its a waste

catalysed sulphite 10-30 ppm

Boil your water for some time before you use it as make up, so you don't add unneeded dissolved gasses. Add just the right amount of treatment and make up with that.

Find a volatile steam treatment you can add
and keep an eye on condensate returns pH and TDS

You shouldn't need to DI or soften your water if that treatment is for hard water, good feed water and better treatments are superior however.

Where do you work, does your employer have a larger boiler with chemical treatment, make friends with the boiler man. See what they are doing. If its a decent size I'm sure they could spare a few mils of treatment. You could also look at their test record and see what treatment programme they are running.

Get a log book keep track of stuff

How much water you add(If you don't do any blow down, constantly add water, and know your system volume you can use this to figure out your cycles etc) , tests of water (ideally pH, TDS, sulphite, p2 alk, PO4), condensate (pH, TDS if you worried about steam side corrosion) and when you have flushed and cleaned the system etc. The logs will give you an idea of how long your sulphite is lasting etc. The trouble with an all in one is just what you notice your sulphite is low, every thing else might be still in the sweet spot so you add more and get every thing too concentrated and it starts to foam and carry over small amounts of boiler water or worse. With your Product query ask them what the ideal parameters are for your feed water (soft/hard) max impurities. Ideal boiler water PO4 levels, pH etc.

My guess with a small boiler like that is you wouldn't even need to blow down as annual draining and cleaning should be enough. Do a good job of cleaning, the sludge in the bottom can set like concrete if left to dry.

On/off seasonal operation isn't great for boilers but that's just the way it is.

[Edited on 10-1-2015 by feacetech]




Sadly, nothing at work but forced hot air.

I find your comment about sulfite interesting. Another water treatment company, Rhomar makes products for steam boilers. They have an all in one product as well and from what I recall, the main thing they recommend is testing sulfite levels.

What does sulfite do in a boiler and where is mine currently coming from?

[Edited on 1-10-2015 by ChrisJ]

ChrisJ - 9-1-2015 at 17:19

Here is a PDF to Rhomar's 903 boiler treatment.

To me, their instructions look far more professional and it just seems like it's probably a better product. The problem is the cost and trying to find a place to buy it.

http://www.rhomarwater.com/media/W-903.pdf

feacetech - 9-1-2015 at 17:23

You have sulphite in you tablets

it is acting as an oxygen scavenger, it reacts with oxygen to form sulphate.

2 Na2SO3 + O2 → 2 Na2SO4

info about oxygen scavengers

http://www.subsport.eu/wp-content/uploads/2012/05/alternativ...

These foreign MSDS sheets cant see what's in the product lucky everything in NZ is more hazardous so it has to be listed :p

[Edited on 10-1-2015 by feacetech]

ChrisJ - 9-1-2015 at 17:29

Quote: Originally posted by feacetech  
You have sulphite in you tablets

it is acting as an oxygen scavenger, it reacts with oxygen to form sulphate.

2 Na2SO3 + O2 → 2 Na2SO4

info about oxygen scavengers

http://www.subsport.eu/wp-content/uploads/2012/05/alternativ...


Ah, interesting!

However, sodium sulphite isn't in the MSDS to these tablets?

1: Sodium Nitrite. % by weight 44.04
2: Sodium Triphosphate % by weight 23.52
3: Sodium Metasilicate % by weight 1.34
4: Citric Acid. % by weight 3.36


It looks like I can buy 5 pounds of it pretty cheap though.
Is this the stuff?

http://www.amazon.com/Photographers-Formulary-10-1341-Sodium...

feacetech - 9-1-2015 at 17:47

Typical hard water treatment programmes have 4 parts

Phosphate/phosphonate treatment
precipitate Mg and Ca Carbonates as serpentine sludge, Carbonates form a concretion layer on the hot surfaces as stated earlier they have retro grade solubility (this is unusual as normally most solids are more soluble in hot water) so when that cold water gets heated at the metal water interface they precipitate out forming and insulating layer over you heating surfaces reducing thermal conductivity and cause something called under deposit corrosion.

caustic (NaOH)
Keeps system alkaline, helps other chemical reactions (can help with magnetite formation), keeps silica volatile (silica is tetrahedral in nature so forms hard coatings sort of like diamond these are not acid soluble and only dissolve in hot caustic slowly)

Dispersant/polymer
keeps the sludge's you make mobile and flowing so when you blow down they leave the system

Oxygen scavenger
remove dissolved oxygen to help prevent corrosion, some also encourage magnetite formation the like the vitamin c analogue erythorbate (Vitamin C is an anti oxidant)

The extra part that you are missing is steam treatment
Typically a filming or volatile amine often a special blend, these travel through the steam system condensing out at different stages and reacting with any acidic condensate (from CO2 as you mentioned earlier)

Some of the other treatments on high purity water use chelation as well/instead of

The word chelation is derived from Greek χηλή, chēlē, meaning "claw"; the ligands lie around the central atom like the claws of a lobster

Ligand could be described as a positive seeking entity with a non bonding electron pair

Basically chelation involves encapsulating on a molecular level the positive ions in solution like a claw grabbing something.

EDTA would be your stereotype chelating agent and coincidently (well not really) is used as the titrating agent in the Mg and total harness testing. The edta binds to the Ca and Mg removing them from the indicator and changing colour once all is consumed

If chelation treatment is done wrong in a high pressure water tube system they can rapidly eat the metals and the protective coatings.


[Edited on 10-1-2015 by feacetech]

feacetech - 9-1-2015 at 17:55


However, sodium sulphite isn't in the MSDS to these tablets?

1: Sodium Nitrite. % by weight 44.04
2: Sodium Triphosphate % by weight 23.52
3: Sodium Metasilicate % by weight 1.34
4: Citric Acid. % by weight 3.36

Opps my bad you have nitrite scavenger theses are typically used in hot water closed loop system in the industrial setting

Basically works the same way Nitrite to Nitrate, however there must be a reason these are not typically used in higher pressure industrial steam boilers.

however its a better at metal passivation than oxygen scavenging

In closed cold water loops bacteria can get the nitrite and make nitric acid which will then lower the pH and eat the metal

You can get nitrite test strips too.

http://www.accepta.com/water-treatment-chemicals-wastewater-...

that might explain why you have nitrite instead of sulphite


[Edited on 10-1-2015 by feacetech]

ChrisJ - 9-1-2015 at 18:06

Quote: Originally posted by feacetech  

However, sodium sulphite isn't in the MSDS to these tablets?

1: Sodium Nitrite. % by weight 44.04
2: Sodium Triphosphate % by weight 23.52
3: Sodium Metasilicate % by weight 1.34
4: Citric Acid. % by weight 3.36

Opps my bad you have nitrite scavenger theses are typically used in hot water closed loop system in the industrial setting

Basically works the same way Nitrite to Nitrate, however there must be a reason these are not typically used in higher pressure industrial steam boilers.

You can get nitrite test strips too.

http://www.accepta.com/water-treatment-chemicals-wastewater-...

that might explain why you have nitrite instead of sulfite

[Edited on 10-1-2015 by feacetech]

[Edited on 10-1-2015 by feacetech]


Ah ok.
I also should have mentioned, my boiler has rubber gaskets between the sections so anything that can harm rubber is out of the question.

Many have steel push nipples, but Weil-McLain has always used gaskets. When I bought the boiler I had found most if not all home steam boilers failed from rotting and practically none failed from gaskets leaking so I didn't really care about the steel push nipples "feature" some brands brag about.

However, I think it is a concern when it comes to using treatment. The Steamaster tablets say they are safe, so I went ahead and started using them.

Will buy some nitrite testing strips.

feacetech - 9-1-2015 at 18:11

you could get the sulphite as well for good measure

Just be aware it will lift TDS in the form of sulphates

it wont be as good as catalysed sulphite but you can add it to any treatment

Then you'll get passivation and two forms of oxygen scavenger.

[Edited on 10-1-2015 by feacetech]

ChrisJ - 9-1-2015 at 18:12

What levels of nitrite am I likely testing for?

Also, is there any chance the violet color is actually showing nitrite levels? If so, is there any test I can do to confirm it?

feacetech - 9-1-2015 at 18:15

do the pH test first its most likely a pH indicator

off the top of my head im not sure what level of nitrite is good I think it was higher than sulphite

I think cold water I use to look for 50-100 don't quote that though

you will have to query from the manufacturer a quick look on the net gave me all sorts of answers one was 1000ppm but sometime these guys want you to use more than you need

http://www.nucalgon.com/assets/prodlit/3-87.pdf

[Edited on 10-1-2015 by feacetech]

ChrisJ - 9-1-2015 at 19:13

Quote: Originally posted by feacetech  
do the pH test first its most likely a pH indicator

off the top of my head im not sure what level of nitrite is good I think it was higher than sulphite

I think cold water I use to look for 50-100 don't quote that though

you will have to query from the manufacturer a quick look on the net gave me all sorts of answers one was 1000ppm but sometime these guys want you to use more than you need

http://www.nucalgon.com/assets/prodlit/3-87.pdf

[Edited on 10-1-2015 by feacetech]


Can I use baking soda instead of Ammonia? I have vinegar and baking soda on hand and can do the test right now.

I'm assuming I should use vinegar and not bleach?

ChrisJ - 9-1-2015 at 19:39

Ok so I took a small bit of water I had left over from when I did some maintenance.

The dose didn't seem very high because the color was faint but I figured it was good enough for now.

As soon as I added white vinegar it turned a pale blue color. The issue is I may have added too much vinegar, or, baking soda is not the right choice.

Right now all I have is cloudy blue water, can't get the violet back. I have plenty more water on hand to do further testing.

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ChrisJ - 9-1-2015 at 21:38

Did some more tests, apparently baking soda is a joke when it comes to pH?

Best I can tell, the stuff turns purple when the pH is an 8 or 9. At 7 it was still blue and the only way I could test this was backwards so far, kept adding vinegar until it turned blue while checking the pH occasionally.

Adding more of the tablet will bring it back to purple, but it ends up darker as well, I assume due t more of the pH indicator being added?

If I buy some ammonia, will that be what I need to confirm this?


Also took a picture of the tablets in their natural form.

[Edited on 1-10-2015 by ChrisJ]

IMAG3500.jpg - 733kB

feacetech - 10-1-2015 at 00:45

dish wash powder has caustic

aga - 10-1-2015 at 12:11

... Caustic Soda, aka Sodium Hydroxide = powerful Base.

Edit:

put the jug on a sheet of White paper - the liquid colour in the photos will be clearer !

[Edited on 10-1-2015 by aga]

ChrisJ - 10-1-2015 at 13:33

Quote: Originally posted by aga  
... Caustic Soda, aka Sodium Hydroxide = powerful Base.

Edit:

put the jug on a sheet of White paper - the liquid colour in the photos will be clearer !

[Edited on 10-1-2015 by aga]


Sorry, I didn't see your request before doing this test.

Using ammonia worked. I guess this means it's without a doubt a pH indicator?

The pictures in order are.

Before adding vinegar
After adding vinegar
After adding a little ammonia
After adding more ammonia.

Adding more ammonia made the color more vivid but not darker. I'm curious though, if adding these tablets "until the water turns violet". If you have a low pH, you would have to add more tablets but you would also be adding more of the chemicals that cause foaming. Isn't this a problem?




A1.jpg - 1012kBA2.jpg - 1.1MBA3.jpg - 1.1MBA4.jpg - 1MB

aga - 10-1-2015 at 13:50

You got it !

Your experiment proves it.

Clearly a pH indicator is One component of the tablets.

The colours are pretty much what you see with red cabbage juice.

feacetech - 10-1-2015 at 15:05

some of the other all in one treatment suggest that if treatment reserves are low, slowly adding small amounts of treatment over time (weeks) if large slug doses cause foaming.

But now you also know that you cant rely on the colour alone

Imagine your water was exceptionally Hard, you could quickly consume your phosphate reserves but the alkalinity of your system maybe fine, you may get caught thinking all is pink no worries!

[Edited on 10-1-2015 by feacetech]

ChrisJ - 10-1-2015 at 19:01

Quote: Originally posted by feacetech  
some of the other all in one treatment suggest that if treatment reserves are low, slowly adding small amounts of treatment over time (weeks) if large slug doses cause foaming.

But now you also know that you cant rely on the colour alone

Imagine your water was exceptionally Hard, you could quickly consume your phosphate reserves but the alkalinity of your system maybe fine, you may get caught thinking all is pink no worries!

[Edited on 10-1-2015 by feacetech]


What consumes the sodium nitrite? I'm going to assume oxygen?

So, sodium nitrite, does it prevent corrosion because it's an oxygen scavenger, or is it a totally separate thing?


feacetech - 10-1-2015 at 21:50

technically its a better metal passivator. It will consume some oxygen but nothing like a dedicated oxygen scavenger


it will be consumed by metal in the system and some O2

ChrisJ - 12-1-2015 at 09:53

Quote: Originally posted by feacetech  
technically its a better metal passivator. It will consume some oxygen but nothing like a dedicated oxygen scavenger


it will be consumed by metal in the system and some O2


So,
If I buy this, would it work in addition to what I'm already using?

10 lb Pail of Sodium Nitrite Food Grade 99+% Pure Granular Free Flowing Food Processing & Manufacturing


http://www.amazon.com/Nitrite-Granular-Flowing-Processing-Ma...


Or, in your opinion would I be better off getting rid of the Steamaster and switching to this as a corrosion inhibitor and oxygen scavenger?

Photographers' Formulary 10-1341 Sodium Sulfite - Anhydrous. 5-pounds

http://www.amazon.com/Photographers-Formulary-10-1341-Sodium...

gdflp - 12-1-2015 at 10:00

I haven't been keeping up with this thread, so I can't answer your question, but sodium nitrite from the same seller can be found directly on their website at a slightly lower cost here. I've ordered from Duda Diesel multiple times and never had an issue.

ChrisJ - 12-1-2015 at 10:23

Quote: Originally posted by gdflp  
I haven't been keeping up with this thread, so I can't answer your question, but sodium nitrite from the same seller can be found directly on their website at a slightly lower cost here. I've ordered from Duda Diesel multiple times and never had an issue.



Appreciate the tip, thanks!

feacetech - 12-1-2015 at 13:03

I would add sodium sulphite as well as your tablets. Unlike Nirtite Sulphite only scvanges oxygen, but it does a better job reacts much faster the downside being no metal passivation.

If you can find catalysed sulphite that would be better, it increases the reaction rate signifcantly.

if you cant get catalysed sulphite i would run a reserve of 30-50 ppm sulphite. this maybe difficult to maintain in a small system testing would be the only way to get an idea of how much to add and how fast it is consumed.

be aware sulphite will rasie tds and once you reach 2000 ppm (conductivty in uS/cm * 2/3) i would blow down and make up untill it got lower. This wont be as bad as the TDS from the concentrated water but its good to keep it down.

Remeber if you pre boil (10-15mins) and treat your makeup before adding this will help.

I would find out from the supplier what ideal nitrite levels are, also monitor these levels.

I would consider changing treatment if you have steam side issues (corrosion, Acidic condensate, Fe in condensate) and find one with a volatile steam treatment included. The makers of your tablets have another product with a steam treament included.

[Edited on 12-1-2015 by feacetech]

[Edited on 12-1-2015 by feacetech]

ChrisJ - 12-1-2015 at 13:12

Quote: Originally posted by feacetech  
I would add sodium sulphite as well as your tablets. Unlike Nirtite Sulphite only scvanges oxygen, but it does a better job reacts much faster the downside being no metal passivation.

If you can find catalysed sulphite that would be better, it increases the reaction rate signifcantly.

if you cant get catalysed sulphite i would run a reserve of 30-50 ppm sulphite. this maybe difficult to maintain in a small system testing would be the only way to get an idea of how much to add and how fast it is consumed.

be aware sulphite will rasie tds and once you reach 2000 ppm (conductivty in uS/cm * 2/3) i would blow down and make up untill it got lower. This wont be as bad as the TDS from the concentrated water but its good to keep it down.

Remeber if you pre boil (10-15mins) and treat your makeup before adding this will help.

I would find out from the supplier what ideal nitrite levels are, also monitor these levels.

I would consider changing treatment if you have steam side issues (corrosion, Acidic condensate, Fe in condensate) and find one with a volatile steam treatment included. The makers of your tablets have another product with a steam treament included.


My concern with this is the entire system breaths in and out of the house. Every time I make steam moist air gets pushed out of all of the vents, bringing any smells with it.

Would steam side protection cause any problems with this?


Sadly, Rectorseal seems to be ignoring my second email just as well as they ignored the first.

I may have to switch to Rhomar or another company that actually provides information and support on their product.

feacetech - 12-1-2015 at 13:26

I wouldnt use steam side protection then your helath is more important than some pipes and valves

ChrisJ - 12-1-2015 at 13:28

Quote: Originally posted by feacetech  
I wouldnt use steam side protection then your helath is more important than some pipes and valves



All of the other previous stuff should be fine though correct?

Sodium sulfate, nitrite etc.

feacetech - 12-1-2015 at 13:43

Yea they are all non volatile.

Is ther any way you can stop the venting of steam and the resulting intake of atmosphere when the pressure drops?

ChrisJ - 12-1-2015 at 14:21

Quote: Originally posted by feacetech  
Yea they are all non volatile.

Is ther any way you can stop the venting of steam and the resulting intake of atmosphere when the pressure drops?


Not so much on a single pipe system.
There are some two pipe systems that run in a vacuum, but single pipe you end up with balancing problems

This is a simplified drawing of how my system works.
Of course piping lengths are different as are radiator sizes and I have two separate mains rather than one, but this gives the overall idea of a single pipe steam system.




ChrisJ - 14-1-2015 at 18:30

So,

Something that is really weird, at least to me, happened.

I had a 5 gallon bucket with maybe a gallon of boiler water in it. It was purple when it started but I went and looked tonight and it's blue. It's been down there for a few weeks now.

What could cause the pH of a bucket of water sitting out in the open to drop several points? It's been cold down there and unfortunately plenty of fresh airflow due to bad drafts. I think it's down to around 50F there now.

Did treatment settle down out of the water causing it's pH to drop, or did something else likely take place?


[Edited on 1-15-2015 by ChrisJ]

feacetech - 14-1-2015 at 23:42

possibly CO2 absorption

the idea was to boil water for 10-15mins to drive off O2

then add treatment then add water while its hot before it cools and absorbs gasses again