HVAC Condensor Issues

Old 04-15-16, 01:46 AM
Thread Starter
Join Date: Apr 2016
Posts: 1
Upvotes: 0
Received 0 Upvotes on 0 Posts
HVAC Condensor Issues

Condensor not coming on not the fan or compressor. I replaced both capacitors and contactor and still nothing. I have a low end multimeter and checked voltage on contactor and im getting a 0. I dont know what else to try. Can anybody please help?
Old 04-15-16, 04:10 AM
Bob14525's Avatar
Join Date: Jun 2013
Location: USA
Posts: 1,554
Received 59 Upvotes on 50 Posts
The first thing I would look for is a fuse for the 24VAC circuit. Not all systems have one, but if it does, it will likely be inside near the transformer or air handler. You can check to see if you have 24VAC at the thermostat. With the thermostat off (or removed from its mounting plate), you should measure ~24VAC between the R and Y terminals on the thermostat.

If you have 24VAC at the thermostat, here's what I would suggest you do next. Turn off the power to the outside unit (there should be an electrical disconnect nearby). Remove the side cover from the outside unit and find where the low voltage control signal (coming from the thermostat wiring) comes into the outside unit. The wiring from the house should connect to the internal wiring via wire nuts.

Remove the wire nuts so you can get your voltmeter probes onto the wires (be sure that they don't touch). With the thermostat calling for cooling, check to see if you have ~24VAC between the two control signal wires. If you do, then the most likely problem is that your system is low on refrigerant and the low pressure switch has opened to protect the compressor.

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: