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Discussion Starter · #1 ·
new (4 months old ) american standard heat pump,,,heats fine ,wont cool, normal head presure, suction in a vacume, after investigating spoke with tech support and determined the txv valve was the trouble, replaced the txv and still same trouble,,was going to replace the line dryer and started to recover the refrigerant, removed exactly one pound and gauges zeroed out,,knowing there was still a few pounds in the system i confirmed this by pressing in the the shradder valves at the reversing valve and yes out came the freon,,so with service valves open gauges at zero and even a vacume pump on it , freon is still in the condenser,,,any ideas as to what would trap it in there like that ????im thinking maybe line dryer but im not sure thats realy the trouble,,
 

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A number of years ago, I had the same issue with an older AC unit. While running, the suction pressure would drop to vacuum. Head pressure would sit. On that unit, there was a restriction in the condenser coil right after the compressor. I had to file an EPA report and cut the line after the compressor to take the pressure off of the coil. After taking pressure off, I ended up blowing over 500 PSI nitrogen to clear the plug. :blink: When it broke loose, it sounded like a shotgun. Needless to say, I replaced the condenser coil shortly after.:gunsmilie:
 

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You could have used a piercing valve, instead of cutting the line open.

OP. If your getting refrigerant out of the schrader at the RV. Connect your recovery machine there.

However. By you post saying that the vapor side was in vacuum. And the head pressure was normal. You might want to check the depressor in your high side hose.
 

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First... I did use the piercer to remove the refrigerant... there was so much pressure behind it that it blew off.

Second... my experience was on an air conditioner. No reversing valve. The pressure was trapped between the compressor and the coil... no place to tie a hose.

Finally...I solved this problem more than five years ago. There was no issue with my depressor in the hose.
 

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First... I did use the piercer to remove the refrigerant... there was so much pressure behind it that it blew off.

Second... my experience was on an air conditioner. No reversing valve. The pressure was trapped between the compressor and the coil... no place to tie a hose.

Finally...I solved this problem more than five years ago. There was no issue with my depressor in the hose.
My reply about the RV and depressor are addressed tot he OP.
 

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Discussion Starter · #7 ·
update,,,after replacing the txv at the air handler suction pressure was in a vacume in both heat and cool,,,with the original txv i had a high head pressure and a normal suction in heat mode but may have not let the unit run long enough for the suction to go into vacume, i recovered the refrigerant from the the tru suction/pressure ports at the reversing valve and had to keep switching between them and the service ports in order to remove it all,,removed line dryer, ( per tech support ) was not the trouble,,,long story short tech support had to call tech support and the 3 of us on the phone determined what i had said early on,,evap coil is clogged,,,going to replace the coil next week,,will update with results,,,thanks guys for your input
 

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Hmmm.

If the coil is clogged. Then in heat mode. You should be able to put your gauges on the liquid line. And see it in a vacuum, or extremely low.

So did you put your gauges on the liquid line while in heat mode.
 
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