PDA

View Full Version : What causes AC compressors to explode on heat pumps?


rkjennison
Jun 1, 2011, 04:37 AM
Can a TXV valve be the cause of an explosion of the AC compressor?

smoothy
Jun 1, 2011, 04:46 AM
Don't most systems have both a high pressure and a low pressure sensor? If the expansion valve stuck shut along with a failure of the high pressure switch... the system could generate enough pressure on the high pressure side to cause a failure at the weakest link.

rkjennison
Jun 1, 2011, 04:55 AM
The AC tech put in a new compressor yesterday, charged the system, and started up the AC unit. The compressor ran for about 30 seconds and shut off. He tried looking everywhere to see if anything was loose or wired incorrectly and finally gave up and said the compressor was "locked up". He was going to order another compressor. Before he left he indicated that the TXV valve was probably the root cause of my compressor blowing up and the releasing of all refrigerant.

smoothy
Jun 1, 2011, 06:39 AM
I'm not an HVAC tech by trade... I do have a license and know enough and have the equipment to repair automotive A/C systems. But the functions are the same.

Since you had a compressor failure... was the system flushed between replacements? Compressor failures usually result in debris that needs flushed out to prevent a recurring failure.

If too much oil was added to the system it will "slug" the compressor resulting in failure. Oil unlike refrigerant isn't compressible.

rkjennison
Jun 1, 2011, 07:17 AM
No, the system was not flushed. The tech mainly took out the blown compressor and said that all refrigerant had been released. He then started putting in the new compressor and relayed that he believed the TXV valve was the failure of my original compressor. I appreciate the input and your time explaining what you believe the problem is.

smoothy
Jun 2, 2011, 06:45 AM
Some systems have filters installed in the refrigerant lines and the debris should have been caught if it did. But one can not assume there are filters installed. The larger the system from what I gather, the more likely filters are there. And in a heat pump because system flow is essentially reversed, you would need two.

A receiver/dryer is not a filter, its function is to remove any trace amounts of moisture that might remain after the system was evacuated with a vacuum pump prior to refrigerant was put in. Moisture + Refrigerant = acid formation. Which will corrode the system from the inside.