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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 5648
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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R22 Ameristar have 128 gh 60 low side in heat mode, switch

Customer Question

R22 Ameristar have 128 high 60 low side in heat mode, switch to cooling and both sides shoot up to 220. tried adding feon but no change. system 1 year old just replaced the contractor the compressor was running all the time with the system off
Submitted: 1 year ago.
Category: HVAC
Expert:  Phil replied 1 year ago.


If you can send me photo's of your gauges attached to the unit so that I can see exactly where they are attached and all of the surrounding piping, compressor and 4 way valve, I can mark it up with coaching instructions.

Use the paper clip icon above to send the photo's

Customer: replied 1 year ago.
The first set of pressures are in heat mode, the last pressures are in cooling mode.
Customer: replied 1 year ago.
both lines feel nearly the same temp
Expert:  Phil replied 1 year ago.


220 psig head and suction pressure makes no sense what so ever on this end, under any fault conditions known to man, or at least me, and I have been around for 55 years so far in this business, the first 35 years with the tools, and the last 20 consulting nationally.

You apparently know how to attach your gauges correctly from the look of it...

If the compressor were OFF when you did the test, then the pressures would equalize at room temprature ranges 100 psig or so... the pressures would only be at 220 psig if the house wire up to 107F inside... that is unlikely, and that would only happen if the house were that warm and the compressor were off.... or if the reversing valve were stuck half way between heat and cool modes... then you would see those pressures, but only if the house were 107F inside... even if you were grossly over charged you would not see those pressures, in cooling mode.

The photo's were excellent by the way, one of them shows condensate on the compressor suction line, that would be running cool in that case, about 65 psig suction pressure... look the system over closely, try another set of gages, 220 psig in cooling mode both suction and head pressure is impossible... we can go from there.

Customer: replied 1 year ago.
I am leaving town tomorrow on business and be back on Monday. I'll try your suggestion and email you Monday. Thank you
Expert:  Phil replied 1 year ago.

Have a safe trip, it will be good to hear from when you get back, you can ignore an notices that say the question has timed out...just report what you can discover, and I will resume with you.

Customer: replied 1 year ago.
I will try your suggested troubleshooting technique tomorrow, thanks
Expert:  Phil replied 1 year ago.

That will work.

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