HVAC system not working

[Lubener]

Thank you, can I replace with a dual to make sure both are replaced? Provided it is a capacitor.

Yes you can as long as the replacement matches the originals in capacity and voltage rating. Most units have a dual, not separate capacitors anyway.

Do you hear the contactor "click"? If not , verify you have voltage applied to the contactor's coil.

I change the cap and contactor out every ten years. If you do that, you likely will never have a breakdown.

 

[maverickfhs]

Compressor does not seem to be running, will order a capacitor and see what happens.

 

[Nick1994]

Compressor does not seem to be running, will order a capacitor and see what happens.

I saw this on Tik Tok yesterday, really good diagnostic video.

 

[dishdude]

I saw this on Tik Tok yesterday, really good diagnostic video.

Too bad it cutoff before he declared the compressor as seized!

 

[Fitter30]

Just kicked in the unit, vents are showing temperature is in 60's while outside is in mid 70's.

15-20 difference is not fully met?

18°to23° difference isn't using outside temp. It's return air at filter and 3' from evap coil. Filter clean and the condenser coil? Did you inspect all the terminals for tightest or being hot?

 

[Fitter30]

Compressor does not seem to be running, will order a capacitor and see what happens.

Appliance parts place should have one. Shape doesn't matter if there's room for it.

 

[CourierDriver]

Currently AC is not blowing cold air - verified filter, outdoor unit and blower inside are running.

Going to validate capacitors shortly, but usually a bad capacitor means outdoor unit won't run? Could it be a sealed system(requires 410a) issue?

Thanks for the pointers.

outdoor condenser fan motors usually will run, but the compressor will not,the startrun capacitors usually blow on the compressor are swollen out and not round - replace it and the compressor will start usually

 

[nomas]

outdoor condenser fan motors usually will run, but the compressor will not, startrun capacitors usually blow start the compressor and are swollen out and not round anymore...try that..

Huh ?

 

[CourierDriver]

Note, if your town has a hvac trade school, u can call them and they send out a senior student to get it running,,,at my school years ago in Chattanooga we would do that,,its a thought

 

[chemman]

Another thing to check is to make sure the wires going to the capacitor and to the contactor have not burned/broken off at the terminals and moved away. I have had to make a new jumper or install a new crimp on terminal a couple of times over the years.

 

[maverickfhs]

Outdoor fan motor is running, replaced the capacitor 40 ones for compressor, but still no condensation on the compressor line - one with a larger nipple.

Any idea what else could it be? How can I check if compressor is running?

 

[Skippy722]

You should be able to hear the compressor run, it has a different sound than the fan. If there’s a contactor you can *CAREFULLY!!!!* push it in manually with a suitable object for a second to see if the compressor comes on.

Depending on your ambient conditions you may not get condensation on the suction line (the larger usually insulated line). The liquid line (smaller uninsulated line) should be warm.

 

[97prizm]

Currently AC is not blowing cold air - verified filter, outdoor unit and blower inside are running.

Going to validate capacitors shortly, but usually a bad capacitor means outdoor unit won't run? Could it be a sealed system(requires 410a) issue?

Thanks for the pointers.

Oddly enough check the batteries in the thermostat. A month ago I came home and my house wasn't cooling. The A/C said it was on but nothing. I turned off the thermostat put new batteries into it and it was back to working.

 

[maverickfhs]

You should be able to hear the compressor run, it has a different sound than the fan. If there’s a contactor you can *CAREFULLY!!!!* push it in manually with a suitable object for a second to see if the compressor comes on.

Depending on your ambient conditions you may not get condensation on the suction line (the larger usually insulated line). The liquid line (smaller uninsulated line) should be warm.

Any idea on the contactor that can be manually pushed? Tested all windings of the compressor too, seems to be fine and not shorted.

There is a unite next to it that is running and it has condensation, so assume this unit should have similar behavior and pattern because of same outdoor temps.

 

[maverickfhs]

Oddly enough check the batteries in the thermostat. A month ago I came home and my house wasn't cooling. The A/C said it was on but nothing. I turned off the thermostat put new batteries into it and it was back to working.

Just curious, if you had outdoor fan and unit was working with batteries issue?

 

[Skippy722]

Any idea on the contactor that can be manually pushed? Tested all windings of the compressor too, seems to be fine and not shorted.

There is a unite next to it that is running and it has condensation, so assume this unit should have similar behavior and pattern because of same outdoor temps.

Can you see a model number anywhere on the unit? I can try to find a wiring diagram based off that.

 

[Nick1994]

Any idea on the contactor that can be manually pushed? Tested all windings of the compressor too, seems to be fine and not shorted.

There is a unite next to it that is running and it has condensation, so assume this unit should have similar behavior and pattern because of same outdoor temps.

If the contractor is bad, I'd think you wouldn't get the fan at all outside either.

Just curious, if you had outdoor fan and unit was working with batteries issue?

If it's kicking on the outdoor fan, shouldn't be an issue.

Feel the compressor carefully. If it's insanely hot, it may be going out or is locked up. If it's warm it should be running. If it is no temperature difference then it probably isn't running.

But a said above, you should know if the compressor is running. They chatter and make noise vs. just the fan outside running.

 

[maverickfhs]

Can you see a model number anywhere on the unit? I can try to find a wiring diagram based off that.

M4AC4030C1000AA, thanks for helping out.

 

[maverickfhs]

If the contractor is bad, I'd think you wouldn't get the fan at all outside either.

If it's kicking on the outdoor fan, shouldn't be an issue.

Feel the compressor carefully. If it's insanely hot, it may be going out or is locked up. If it's warm it should be running. If it is no temperature difference then it probably isn't running.

But a said above, you should know if the compressor is running. They chatter and make noise vs. just the fan outside running.

Thanks - unit is only few years old but definitely no change on temperature and line(condensation one) and not sure if compressor is running so trying to see if we can test it?

 

[SaberOne]

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.