2000 civic A/C

I have a 2000 Honda civic ex. A couple months ago while driving I heard a squeal and my AC was blowing hot. I just changed out my expansion valve, drier and compressor but when I hooked up my guage my low side wouldn’t build pressure and my high sat like 150. Finally the low side got to 20 and high about 200. I over filled trying to get low side right and when I did get it to 40-50 my high side would be 300 but it wouldn’t hold. I emptied the system but 150 psi is somewhere in the high side and won’t get out. Any ideas?

You have liquid trapped on the high pressure side.

Your gauge readings are also showing a plugged/restricted system

If you can get the compressor to run again with a small charge, feel the temperature of the fittings around the system. Start at the compressor outlet, the condensor inlet, the surface of the condensor, the outlet of the condensor, the liquid line to the receiver dryer, the inlet to the receiver dryer, the body of the receiver/dryer, the outlet of the receiver dryer, the inlet to the expansion valve, the evaporator inlet, and the evaporator exhaust i.e. suction line. If you feel a drop in temperature at any of these junctures or see sweat or frost, that is where the restriction is located. It is most likely a plugged receiver/dryer, a clogged expansion valve screen, or a nonfunctioning expansion valve.

Did you flush the condensor and evaporator before you replaced the compressor?

Hope this helps.

I did not flush either my condenser or evaporator… I did blow out my main lines from the high/low side that runs to the evaporator. Do you think I need to replace any of the new parts i put on? Im gonna break the system down piece by piece and clean it out.

If you replaced the compressor because it disintegrated, you probably should still flush out the condensor. You will probably have to replace the receiver/dryer anyway as you will have the system open for servicing. Also see if you can find the expansion valve screen because that may have caught debris that made it past the receiver/dryer filter.

I ordinarily would not flush the evaporator and suction line as debris would not likely get past the filter(s) and the expansion valve. But, flushing the evaporator would be a good precaution against ruining a new compressor.

Let us know how this comes out along with the gory details.