Author Topic: Pumping charge around.  (Read 3185 times)

Offline alb

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Pumping charge around.
« on: August 30, 2011, 07:37:48 AM »
I am doing some development work on a new style heat pump system.  Part of my experimental system involves the use of a mini-split to pump R410 to a new "coil" thru a complex setup of valves, flowmeters, check valves and pressure gauges.  I have the need to occasionally add gauges, etc. on the compressor/condensor side of the service valves.  Because of the setup with check valves, flowmeters, etc., it is very difficult to recover, leak check, evacuate and recharge the whole system.  It would save me a HUGE amount of time if I could pump and store the charge in the evaporator side.

My question:  Is there a way to pump the charge "outside" the condensor that is equivalent (or opposite) to the way you do a pump down?

Any help would be appreciated and I'll see that you get a nice discount when this hits the market.  ;)

Offline Admin

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Re: Pumping charge around.
« Reply #1 on: August 30, 2011, 08:30:55 AM »
I think you will have a hard time storing a charge in the evaporator, because a heat pump system holds more refrigerant that a standard a/c.  You may need to install a accumalator at the indoor coil and install service valves as well.  In theory if you ran the system and closed the suction line valve at the indoor coil, it should force the charge into the evaporator, then close the liquid line valve.

Offline alb

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Re: Pumping charge around.
« Reply #2 on: August 30, 2011, 08:51:38 AM »
I actually have two evaporators connected to my valve setup, so I do have alot of capacity.  My system allows me to pump down and switch between systems, but there's no reason I couldn't open them both up for "storage".

Offline rmuntz

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Re: Pumping charge around.
« Reply #3 on: September 02, 2011, 03:58:16 PM »
I can't see pumping down into the evaps because on start-up you will return liquid to the compressor causing damage.
I'm not sure what you are trying to accomplish here. If you want to install gauges or other periferals why not use access fittings with schreader cores or valved-off access fittings?

Offline alb

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Re: Pumping charge around.
« Reply #4 on: September 05, 2011, 11:20:24 AM »
Just trying to save a labor intensive recovery and evac.  We've got so many flow meters, check valves, etc on the system that it's tough to be positive everything is evac'd.  Because of what we're trying to develop, it would just be better to leave some parts undisturbed.