Any HVAC guys out there?

[Podunkadunk]

The external portion of my air conditioning unit (compressor??/fan) is humming. There are two of them out there, one for upstairs, the other for downstairs. The downstairs unit is making a hum. I've tried to listen to see where it's coming from, but can't tell.

It's pretty pronounced. It's been doing it for a while now. I first noticed it about 6 months ago.

Everything is working fine with the heater/AC...is this something I need to be concerned with?

Thanks

Podunk

 

[Bill Barrett]

Only when unit is running? Without hearing/seeing it I would say contactor.

 

[Podunkadunk]

Bill,
It only "hums" when the unit isn't running, ie. it's between cycles. As I stated before, the heating/cooling works like a champ, it just hums.

I noticed it 6 months ago when cleaning out gutters. Then yesterday again while I was recaulking some windows by the unit.

Podunk

 

[Willis Fecon Bushhogging]

The external portion of my air conditioning unit (compressor??/fan) is humming. There are two of them out there, one for upstairs, the other for downstairs. The downstairs unit is making a hum. I've tried to listen to see where it's coming from, but can't tell.

It's pretty pronounced. It's been doing it for a while now. I first noticed it about 6 months ago.

Everything is working fine with the heater/AC...is this something I need to be concerned with?

Thanks

Podunk

I not a service guy, but sometimes, mine humms at the end of the cycle, nothing else is running, just a hum. My service guy said it was defrosting.
As stated before, I would get it checked, a friend of mine had his house catch fire and burnt up completely, from a faulty a/c unit. (house and unit was only 2 years old)

 

[kenmac]

heat mode or cool mode ??

 

[Podunkadunk]

Kenmac,
Cool mode. We have the thermostat set at 77 and it's been pretty cool out, so the air cond. hasn't been running much.

I was around there today, it was humming and didn't kick on once (in the 60's and low 70's today so it didn't get low enough to cycle on).

Podunk

 

[kenmac]

If there is a transformer on the outside unit ,that could be what your are hearing. I have seen people put a transformer at the outside unit. If not it could be the contractor. If it were in heat mode ,I would say defrost mode. You can cut the power & pull the side panel off where the electrical stuff is located. Turn the power back on & listen for the hum

 

[Sigarms]

Edit, never mind. Trying to trouble shoot over the internet is worse than doing it over the phone.

Contactor or transformer.

 

[gator]

If its a heat pump, from what you describe (in cool mode, not running and hum), sounds like what you are hearing is the coil on your reversing valve. On everyone I ever worked on, its energized in cool mode and deenergized in heat mode (except when defrosting).

 

[kenmac]

If its a heat pump, from what you describe (in cool mode, not running and hum), sounds like what you are hearing is the coil on your reversing valve. On everyone I ever worked on, its energized in cool mode and deenergized in heat mode (except when defrosting).

That's the other item that I forgot to mention