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outdoor r134a walk in suggestions

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Discussion starter · #24 ·
Again running and head masters has nothing to do with it. It's starting . Also agree about not a great set up. However it is what it is, and I have to try and fix it.
 
#26 ·
For units like this, Heatcraft has LPC settings that need to be followed.

R134a isn't commonly used around here because I would have to set LPC to cut out in a vacuum.

Receiver heat is a good idea, as is a LPC bypass time delay control.
 
#27 ·
Ok as far as the cheapest solution.... I'd use the method of heating the receiver described earlier and maybe a timer for LPS. That's the cheap quick way to make it work b/c it sounds like the installer was nuts...

The proper way for me would be headmaster, Tstat, solenoid, and setup for pumpdown.

Oh never mind about the fancycle idea, won't work...long day ha
 
#28 ·
kklobas said:
And I'm sure no installed pressure relieve valve? I may really look at moving indoor or telling them they need to go 404 outdoor unit. A little worried of overheating receiver.
Click to expand...
The pressure relief would be a small fusible plug in the receiver.

What are the odds the owner will think all options are too expensive, and they will decide just to keep a wood box with a space heater over the condensing unit?
 
#35 ·
Heating and insulating the receiver was common in the days of R12. Heat tape would be energized thru an ambient thermostat. The only purpose of heating the receiver is for start up in low ambient conditions. Ideally you would install a head pressure control and make it a pump down system. You can make it work without all the expense by replacing the space heater with a fan cycle and installing a thermostat in series with the LPC. Use the thermostat for box control and LPC for a safety.
 
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Discussion starter · #36 ·
2sac would it still flow on start up with tsat at say 0 degrees ambient without heat taping receiver? An old timer i talked to later today said same thing r12 and any of the r12 replacements they would just heat tape and replace lp control with tstat for a cheap fix
 
#37 ·
kklobas said:
2sac would it still flow on start up with tsat at say 0 degrees ambient without heat taping receiver? An old timer i talked to later today said same thing r12 and any of the r12 replacements they would just heat tape and replace lp control with tstat for a cheap fix
Click to expand...
At 0*F ambient if the unit has been off for a while and acclimated, it will only get started if your LPC is set for cut in about 6 PSI. :eek2:
 
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kklobas
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