ManyInterests
National Hazard
Posts: 930
Registered: 19-5-2019
Member Is Offline
|
|
Mantle no longer heating after spill
One of the main problems I had with my heating mantle (and I owned two so far... I might be forced to get a replacement...) is the issue of what
happens when a spill occurs.
On my one liter mantle and two liter mantles, I had sulfuric acid spills and methanol spills that I was able to repair, by washing out the mantle with
bicarbonate water and then a lot of distilled and tap water to get that out. I was able to fully restore my mantle with minimal damage.
If I tried to power it on while it had some acid or other non-pH neutral stuff on it, I would see the wires start to flare beneath it and I would turn
it off immediately to prevent damage.
However today I had a very, very minor spill. When boiling down sodium nitrate solution a few drops hit the side of my mantle and I did pour water and
rubbed it with paper towels to clean it. There was some very minor flaring on the absolute top of the sleeve, I thought it was no biggie and I just
let it be. but then it stopped heating. On the LED display it goes from 'PE' to the temp and so on and so forth. It does not heat up. I tried to let
it dry off from the liquid and while it isn't 100% dry yet, it still isn't wanting to heat up.
Did I blow a fuse? I'll have to dismantle it and see. What else do you think could have caused this issue? I find it really ironic that it was a bit
of sodium nitrate solution that caused it to go down when it had a remarkable amount of sulfuric acid fall on it and it still survived.
|
|
|
Rainwater
National Hazard
Posts: 919
Registered: 22-12-2021
Member Is Offline
Mood: indisposition to activity
|
|
Check the fuse first, if thats good
Then test the heating element, If thats good, next is the power triac.
If the heating element its not good, you need to find and fix the break
If the triac is bad, it will need replacing. Which is not too difficult.
Some systems do not use a triac. They will use a power fet or relay.
[Edited on 11-12-2023 by Rainwater]
"You can't do that" - challenge accepted
|
|
|
Sulaiman
International Hazard
Posts: 3695
Registered: 8-2-2015
Location: 3rd rock from the sun
Member Is Offline
|
|
The nitrate salt can easily form unwanted conductive paths on PCBs,
so if the above fails (or even if it works) look for signs of corrosion or salt deposits on the electronics,
If visibly present (or not) thoroughly washing the electronics with tap water,
(and optionally a wash using liquid detergent)
followed by a rinse with distilled water, may help.
If no distilled water is available then after washing,
dry as quickly as you can,
using a blast of air (eg a hair dryer set to cold) to remove as much water and moisture as you can,
then dry using warm air (<80oC), or sun-dry etc.
Transformers and potentiometers/variable resistors are difficult to dry so try to not get them wet.
Pcb mounted buzzers are washable IF you cover the hole with self-adhesive tape.
Good luck.....
CAUTION : Hobby Chemist, not Professional or even Amateur
|
|
|
ManyInterests
National Hazard
Posts: 930
Registered: 19-5-2019
Member Is Offline
|
|
| Quote: |
If no distilled water is available then after washing,
dry as quickly as you can,
using a blast of air (eg a hair dryer set to cold) to remove as much water and moisture as you can,
then dry using warm air (<80oC), or sun-dry etc. |
Yeah I wasn't able to dry it quick enough. I need to mention that the water did not touch the electronics. Those are WELL insulated. But I will try to
do that. I will get more distilled water. A lot more.
|
|
|
ManyInterests
National Hazard
Posts: 930
Registered: 19-5-2019
Member Is Offline
|
|
So a quick update. After coming home, I used around a cup of distilled water to wash it and I used a dryer to mostly dry it (there is still a bit of
moisture left) there is no improvement, meaning tomorrow I will need to begin disassembly of the device.
I need to mention that it powers on just fine, the stirrer also appears to be functional (needs some testing to prove it though) and it is just that
it won't heat. I will disassemble it and photograph all the parts and post them here tomorrow.
|
|
|
ManyInterests
National Hazard
Posts: 930
Registered: 19-5-2019
Member Is Offline
|
|
Guys, the mantle's sleeve was burned out, and thanks to anti-repair stuff by the manufacturer, replacing the sleeve is more trouble than it's worth.
Oh well, I was gonna buy some stuff for Christmas... so the funds are now rerouted to what will be (hopefully) my final mantle.
|
|
|
semiconductive
Hazard to Others
Posts: 325
Registered: 12-2-2017
Location: Scappoose Oregon, USA.
Member Is Offline
Mood: Explorative
|
|
silicone caulk mixed with ethyl-acetate can make a liquid that coats fiberglass circuit boards. I make a good liquidy mixture with it, and dip a
circuit board into it wires and all. Allow it to cure, and redip a few times to get a nice thick coating.
I use it to water-proof circuit boards for use in rivers, etc, without shorting.
I don't know if that might help increase chances of a PCB surviving an acid spill or not. I imagine adding powedered teflon might increase the chances
of it resisting acid for a short period of time. But if you feel experimental, you already have a damaged circuit board you could test the coating
on. Just a thought...
|
|
|
Sulaiman
International Hazard
Posts: 3695
Registered: 8-2-2015
Location: 3rd rock from the sun
Member Is Offline
|
|
Quote: Originally posted by ManyInterests  | | Guys, the mantle's sleeve was burned out, and thanks to anti-repair stuff by the manufacturer, replacing the sleeve is more trouble than it's worth.
|
It may be worth 'fixing' that mantle,
even a temporary fix may be worth it
as a potentially sacrificial mantle
in cases where you'd rather not risk your new one?
CAUTION : Hobby Chemist, not Professional or even Amateur
|
|
|
ManyInterests
National Hazard
Posts: 930
Registered: 19-5-2019
Member Is Offline
|
|
It's done and tossed away. At any rate, I did find ways of working with some other material so I can only use my mantle when I absolutely must.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
