In this troubleshooting situation you have responded to a complaint that a 4-ton package unit air conditioner is not cooling. When you arrive, you find that the indoor air handler is running, the ...

The compressor is the heart of any air conditioning or refrigeration system, so when it starts showing signs of not working correctly, technicians must act quickly in order to find out what is wrong.

Since this column's inception, we've received a substantial number of questions concerning air-conditioning troubleshooting. Answering each one would take quite some time, but we will attempt to ...