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Discussion Starter #1 (Edited)
I am still somewhat new in the field and learn something new every day.

Todays delima is a 12yr old carrier heat pump. I have checked the thermostat programming. The air handler is fully functional, evap is clean, air filter is new, blower is working. Auxiliary heat is functioning. The issue is within the heat pump itself.

Manifold gauges are connected, indoor ambient temperature is 72* , outside ambient at the coil is 30*. Carrier charging chart for these temps provide with low pressure of 79 and high pressure of 293.

With the heat pump running continuous approx 20 minutes my low side pressure is 80 and high side is 225. High pressure line temp fluctuates between 96-103.

Normally a low high pressure line temperature would indicate to me the system is overcharged. If i recover refrigerant the temp drops, if i add refrigerant the temp will max out at 106 before dropping below 100.

I failed to mention the outside coil is clean.

Ok, back to the issue... I'm leaning towards possible refrigerant blow-by in the reversing valve, or possibly compressor failure. What's your thoughts?
 

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An RV that has internal blow by/leakage, would also cause the low side pressure to be high.

Is the LLFD inside or outside of the cabinet. Are checking the high side pressure at the liquid service valve, or the hot gas service valve.
 

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Discussion Starter #3 (Edited)
An RV that has internal blow by/leakage, would also cause the low side pressure to be high.

Is the LLFD inside or outside of the cabinet. Are checking the high side pressure at the liquid service valve, or the hot gas service valve.
Thanks for the quick response
Happy New Year!

The LLFD is located outside the cabinet, checking high pressure on gas side in heat mode.
 

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See how much of a preesure difference there is between the 2 lines. Could have a slight pressure drop.
 
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