Jerbanzo bean
Harmless
Posts: 4
Registered: 28-3-2017
Member Is Offline
Mood: No Mood
|
|
Pump for condenser and aspirator
Hi, I've been running my 400mm condenser with a real cheap submersible aquarium pump. It got the job done perfectly fine but recently kicked the
bucket  I also sometimes use a water aspirator.
To save on my water bill I was wondering if I could just run a strong enough pump through my aspirator. If I can, I could get a little valve to lower
the pressure when I'm using the pump for my condenser. Has anyone has any experience using a pump for their water aspirator?
Bonus question; do you think I could use both at the same time with a splitter after the aspirator? I think there might be a way to get just enough
pressure to use both and not have too much pressure after the aspirator to mess with the vacuum. Just guessing here 
|
|
|
JJay
International Hazard
Posts: 3440
Registered: 15-10-2015
Member Is Offline
|
|
I've done that before with tap water, but I definitely prefer to use a tap and a pump or perhaps two pumps. You want pretty high water pressure for a
high vacuum; while your aspirator may start functioning at well below 15 psig, to pull the most effective vacuum, you want much higher water pressure,
and it can be scary running that kind of pressure through your condenser.
|
|
|
XeonTheMGPony
International Hazard
Posts: 1640
Registered: 5-1-2016
Member Is Offline
Mood: No Mood
|
|
Well you can providing the pump is large enough and can handle the flow and pressure (You can find this info on the pumps head curve)
When controlling pressure ideally you never want to dead head the pump so you bleed pressure by diverting valve, this diverter can feed the condenser,
Alt: You can have two diverter valves to independently control pressure and flow through the condenser.
from here it gets complex with buffer tanks to remove pulsations from diaphragm pumps and pressure regulating valves.
------Condenser----Pressure
----------^--------------Bleed
----------^-------------^
------- Valve---------Valve
Pump > ^-------------^----> Aspirator
Simpler if possible is a 3 way diverter valve as it will automatically balance when you want more condenser flow Vs more pressure bleed off.
Alt:
--------------------------------Condenser
----------------------------------------^
----------------------------------Globe valve
----------------------------------------^
---------------------------------------PRV
Pressure pump > Buffer tank >--^---> Globe valve > Aspirator
[Edited on 29-3-2017 by XeonTheMGPony]
[Edited on 29-3-2017 by XeonTheMGPony]
|
|
|
Sulaiman
International Hazard
Posts: 3695
Registered: 8-2-2015
Location: 3rd rock from the sun
Member Is Offline
|
|
I have been using a 5 way valve (intended for aquarium air supply) for vacuum,
so must be good for water I guess.
cheap e.g. http://www.ebay.co.uk/itm/1-2-3-4-5-Way-Air-Flow-Distributor...
CAUTION : Hobby Chemist, not Professional or even Amateur
|
|
|
XeonTheMGPony
International Hazard
Posts: 1640
Registered: 5-1-2016
Member Is Offline
Mood: No Mood
|
|
Sadly not even close for the volume of flow, remember water is 800 times more dense then air this friction losses amount to a huge number in such
manifolds, globe valves are required as they where built for throttling so provide smooth adjustments, ball valves get eaten up from cavitation
erosion over time.
All the pump lines should be 1/2 as with the valves and only bush down to where the tube connect
But for low flow systems those are a nice looking valve! be good for air supply setups for the lab
|
|
|
Jerbanzo bean
Harmless
Posts: 4
Registered: 28-3-2017
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by XeonTheMGPony  | Well you can providing the pump is large enough and can handle the flow and pressure (You can find this info on the pumps head curve)
When controlling pressure ideally you never want to dead head the pump so you bleed pressure by diverting valve, this diverter can feed the condenser,
Alt: You can have two diverter valves to independently control pressure and flow through the condenser.
from here it gets complex with buffer tanks to remove pulsations from diaphragm pumps and pressure regulating valves.
------Condenser----Pressure
----------^--------------Bleed
----------^-------------^
------- Valve---------Valve
Pump > ^-------------^----> Aspirator
Simpler if possible is a 3 way diverter valve as it will automatically balance when you want more condenser flow Vs more pressure bleed off.
Alt:
--------------------------------Condenser
----------------------------------------^
----------------------------------Globe valve
----------------------------------------^
---------------------------------------PRV
Pressure pump > Buffer tank >--^---> Globe valve > Aspirator
[Edited on 29-3-2017 by XeonTheMGPony]
[Edited on 29-3-2017 by XeonTheMGPony] |
Hmm yes this does look good. I like your solution with the buffet tank especially.
|
|
|
Jerbanzo bean
Harmless
Posts: 4
Registered: 28-3-2017
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by JJay | | I've done that before with tap water, but I definitely prefer to use a tap and a pump or perhaps two pumps. You want pretty high water pressure for a
high vacuum; while your aspirator may start functioning at well below 15 psig, to pull the most effective vacuum, you want much higher water pressure,
and it can be scary running that kind of pressure through your condenser. |
A buddy of mine does odd jobs. He scraps a lot of HVAC equipment and told me he could get me a condenser out of a fridge or dehumidifier pretty
easily. I might just start on the condenser to vacuum project I've been planning out and buy another cheap aquarium pump.
Might be cheaper over all and most likely more effective and a longer lasting solution.
|
|
|
XeonTheMGPony
International Hazard
Posts: 1640
Registered: 5-1-2016
Member Is Offline
Mood: No Mood
|
|
a refrigerant condenser is a gas to gas exchanger, with care full cleaning you can us them as a gas to water Hx but being copper and aluminium not
sure what you can do chem wise with it.
Less you're going to use it as a heat rejection source for your water after the glass condenser int he lab, but then you need an isolated circuit! As
any corrosive gasses absorbed into the water from the aspirator will make fast work of the riffled copper tubing! (Lots of surface area!)
|
|
|
Jerbanzo bean
Harmless
Posts: 4
Registered: 28-3-2017
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by XeonTheMGPony | a refrigerant condenser is a gas to gas exchanger, with care full cleaning you can us them as a gas to water Hx but being copper and aluminium not
sure what you can do chem wise with it.
Less you're going to use it as a heat rejection source for your water after the glass condenser int he lab, but then you need an isolated circuit! As
any corrosive gasses absorbed into the water from the aspirator will make fast work of the riffled copper tubing! (Lots of surface area!)
|
I'm actually going to just pull a vacuum with the condenser rather than use my aspirator. I think it would hold up for a while, but yes I'll probably
damage it with anything corrosive that ends up not getting trapped in my condenser.
|
|
|
XeonTheMGPony
International Hazard
Posts: 1640
Registered: 5-1-2016
Member Is Offline
Mood: No Mood
|
|
How on earth do you do that with a coil of copper?!
All cooling systems using the Carnot cycle have an evaporating coil, a metering device, a compressor and a condensing coil.
I can not think of any way you'd make any vacuum using a coil of fined copper, so I'll go on a limb and guess you mean the:
Compressor
[Edited on 31-3-2017 by XeonTheMGPony]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
