Curious unit is usually completely shutt off if there is an issue like that with drain line, was that the case? Like unit would not run at all, including outdoor one.My home unit stopped working yesterday afternoon when it was 114°. Did the usual troubleshooting and cheetah flips but I couldn’t figure it out. Called the Tech and he knew right away where the problem was. Apparently, the condensation drain line was clogged, which tripped the safety circuit, so it wouldn’t flood the system. Flushed out the line and I was up and running again.
HVAC system not working
- Thread starter maverickfhs
- Start date
Some contactors have a cover on them, you have to remove it to be able to push them.
Yeah the fan and everything kicked on but the A/C wouldn't blow cold. The thermostat said the A/c was on.
The contactor will be near where the electrical connection is. No high/low pressure cutouts for AC models. If the fan is coming on it’s fine though.
I’m thinking it’s either a compressor problem or low/out of refrigerant. Possibly a TXV problem if you have one…. You’ll have to call someone for those problems.
@Skippy722 thanks for checking.
How can I validate if compressor is kicking in or no? Because I confirmed all three windings are not shorted and have continuity on them.
Any other thing I can check or troubleshoot before calling da man?
How can I validate if compressor is kicking in or no? Because I confirmed all three windings are not shorted and have continuity on them.
Any other thing I can check or troubleshoot before calling da man?
If the fan is kicking on but the compressor isn’t, I think you have a compressor problem. It’s possible a thermal overload switch has failed… I know you said there was continuity but did you check for a short to ground and what was the resistance values?
Testing if an HVACR Compressor is Shorted to Ground, Open, or the Thermal Overload is Tripped!
In this HVAC Training Article, I discuss how to perform electrical troubleshooting on an HVAC/R compressor to determine if it is bad. Too many times, compressors are condemned without taking the proper measurements to verify that they are damaged. To help prevent this, I wanted to cover how to...
www.acservicetech.com
When you turn on the system, you should hear the compressor over the fan. It will be a very obvious 60Hz growl/buzz that gets quieter over the next couple of seconds.
Did follow the and did not see any short to ground either. Will check actual resistance values too and post here.If the fan is kicking on but the compressor isn’t, I think you have a compressor problem. It’s possible a thermal overload switch has failed… I know you said there was continuity but did you check for a short to ground and what was the resistance values?
Testing if an HVACR Compressor is Shorted to Ground, Open, or the Thermal Overload is Tripped!
In this HVAC Training Article, I discuss how to perform electrical troubleshooting on an HVAC/R compressor to determine if it is bad. Too many times, compressors are condemned without taking the proper measurements to verify that they are damaged. To help prevent this, I wanted to cover how to...
Any idea where is thermal switch located?
Definitely not hearing it - only fan motor is being kicked on. Thanks
You can disconnect the fan wires from the contactor and turn the system for a few seconds if you want to be sure. You'll definitely be able to hear what the compressor sounds like--if it's making any noise at all.
Thanks, can it overheat or kill anything on the compressor ?
Thermal switch is probably internal to the compressor. Just bumping it on for a brief moment to hear it won’t hurt anything.
If you ran it long enough without the fan it could overheat the compressor, which would trip the internal thermal switch (which would reset when the compressor cools off) but that would take longer than the few seconds it would take for you to hear if the compressor is doing anything.
Okay so tested everything and no issues with compressor.
Changed the capacitor for compressor, initially compressor pipe got cold for a few mins and then nothing(no condensation and not any more cold).
Thermostat is sending voltage and contactor is working well too.
Changed the capacitor for compressor, initially compressor pipe got cold for a few mins and then nothing(no condensation and not any more cold).
Thermostat is sending voltage and contactor is working well too.
Yes sir-ree! The entire system did shut down, including the digital thermostat. Like you said, it’s designed to do that to prevent backflow and flooding. I just knew it had to be something simple, but I just didn’t think to look at the drain line.
So to follow up on SaberOne's comments about the condensation shut off switch, that is going to be near your airhandler/furnace inside the house, not at the a/c condensing unit outside the house.
Usually a drain pan switch, or a pump cutoff switch, depending on how your condensation drain line is setup.
Since your system started and ran for a few moments, that could either be the switch being tripped, or your system has an issue that is causing the low or high refrigerant pressure switches to trip. Could be a low refrigerant issue.
Honestly, at this point, if you can't locate the condensate drain switch and determine that as your cause, you need to call a professional.
Usually a drain pan switch, or a pump cutoff switch, depending on how your condensation drain line is setup.
Since your system started and ran for a few moments, that could either be the switch being tripped, or your system has an issue that is causing the low or high refrigerant pressure switches to trip. Could be a low refrigerant issue.
Honestly, at this point, if you can't locate the condensate drain switch and determine that as your cause, you need to call a professional.
I did find the condensate drain switch(rectorseal) outside the coils(furnace area) - cleaned the trap, poured bleach and clean water in it to clear it.
Still suspecting it is something small that is tripping and causing compressor to stop after few seconds.
Need a meter with an amp clamp to see if the compressor is pulling amps. The fan itself will pull about an amp.
I dont think you have a contactor issue as the fan wouldn't be running. Also not a drain switch issue either because you have the fan running which means you are getting control power to the outdoor unit.
I'm guessing its low on charge.
I dont think you have a contactor issue as the fan wouldn't be running. Also not a drain switch issue either because you have the fan running which means you are getting control power to the outdoor unit.
I'm guessing its low on charge.
A cover would have probably kept out the ants that gummed up the last contactor that I replaced.
Fun fact..the term "bug" as in "software bug" apparently originated from an insect that got stuck in a relay on one of the first relay-logic computers.
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