HVAC repair advice needed

[zman]

A friend of mine called and said they had a blackout and when the power came on his outside compressor stopped working. He called me because I am an electric motor/electrician but I have never dabbled in HVAC units.
He says the fuses next to the unit are good and there is a Hum from the fan but no power. In the motor world this can be one leg of the 220V is broken/blown or a start capacitor or a bad motor. Seems a quik google search points to a blown capacitor as most likely cause, I have seen plenty of blown capacitors so Identification is no problem, should I use my meter I`ll discharge it.
Is there anything else inside that I should look at? It is a Payne model PA12NA024/Series: G.
Thanks for any advice.

 

[TossingLead]

Looks like you are on the right track. Check the contactor also.

 

[dan filipi]

Well check first your getting 240 to the 2 pole contactor then push the contactor closed. The compressor should start up.
If it does then the contactor's low voltage coil could be bad not pulling the contactor closed.
Could also be 24 volts isn't getting to the contactor from the thermostat to close it.
Check your getting 24 volts at the low voltage connectors at the contactor with the thermostat set to cool.

 

[zman]

Thanks, I`ll check the contact/relay..From what he described it has a push in pull out fuses mounted right next to the unit, I guess your saying there is a contact or relay further along the main feed?

 

[dan filipi]

zman » Tue Aug 27, 2013 4:28 pm[/url]":1ux60kvf]
Thanks, I`ll check the contact/relay..From what he described it has a push in pull out fuses mounted right next to the unit, I guess your saying there is a contact or relay further along the main feed?

The push in pull out is just a safety/service disconnect, the contactor is inside the unit cabinet where the compressor and fan are.
Follow the conduit from the disconnect to the unit, the contactor is inside there.

 

[zman]

I think I got it, the panel inside the home sends a 24V signal to the relay that turns on the fan, something like that.

 

[dan filipi]

If the condenser fan is running then 24 volts is reaching IT but there could be a problem with 24 volts not reaching the compressor contactor to tell it to close and start up the compressor.

 

[slabghost]

Check to see if his stove works. If not he may have lost a leg of the house feed.

 

[zman]

slabghost » Tue Aug 27, 2013 5:05 pm[/url]":c1nxnapf]
Check to see if his stove works. If not he may have lost a leg of the house feed.

I`m hoping it is that easy, lord knows I made allot of money re setting breakers.

 

[zman]

A capacitor is all it needed, thanks for the advice guys.