A few days ago, it started using the heat strips constantly where it seldom had ever used the strips and the air handler runs constantly to keep up. OD temps in the 40's which should be easy for it. All of the lines inside the unit felt cool at about equal ambient temp. I pulled the diagrams and checked the pressures and found both pressures equal about where they should be for static ambient temps with R22. The thermostat is calling for heat and the contactor to the compressor is closed.
I checked again yesterday with temps in the upper 60's in cool mode. Found the same - thermostat calling for cooling and the compressor contactor closed with voltage to the compressor feeds. Pressures are equal around 135psig. Could not detect compressor running. (I don't hear well) Voltage from contactor to compressor at 127 volts phase to ground and 248 volts phase to phase which tells me the compressor should be running. Checked for continuity in compressor with feeds disconnected from contactor and found both legs at infinity. The pressure sensor on the compressor is closed. If I am reading all of this correctly, the compressor is dead.
The reason I am asking is that the unit was not cooling well in the fall. I had the service folks who installed the unit when we built on 2000 out several times to check it. Even though I was seeing what I believed to be low pressures, they informed me this was OK. When I first started having cooling problems, I was getting pressures like 150/82 on a 90 deg day with the unit running constantly. I have already spent over $500 trying to get this resolved with the service folks and the only thing they have done is test and add refrigerant. The pressure have never increased above about 180 on the high side although the low side was about 125 the last time I know the compressor was running while being checked. This is an R22 system. I think the compressor has been limping for some time. Am I missing something or is it time to replace at least the compressor? Is a 6 year old system even worth a compressor when install labor is considered?
Any ideas or pointers greatly appreciated.