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After power cut, no cold air

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michaeljc70:
I accidentally shut off the power at the circuit breaker for my furnace (not condenser) while looking for the circuit for something else. The a/c was on.

After turning the power back on, my a/c was not blowing cold air and the unit outside was not on. I went back to the circuit breaker and the double circuit for the a/c condenser was not all the way to off, but not all the way to on either, like it had been triggered off.

I flipped it to ON and turned the A/c on. The condenser turned on (well, at least the fan on top of it), but no cold air. I also heard a surge every few minutes. I have always heard a surge when first turning the a/c on.

I repeated turning the a/c on/off from the thermostat and still room temp air. Even tried turning it to heat, waiting, turning it back to a/c.

Any ideas? Could cutting the power to the furnace but not the condenser have fried something?

JWWebster:
You might have a burnt wire on the compressor. Sometimes a brief interruption can cause a terminal wire to melt. I would check for a fail compressor capacitor. Might be that the fan motr has a sep cap or that the fan side of the cap is ok. Could be a contact on the magnetic contator has been fried.
My page: https://sites.google.com/site/sublimeappliancerepair/ask-the-sublime-one-a-question/outside-condenser-blues

haroldsappliance:
Time delay could be faulty. Power off and then right back on is not good, hence the time delay component. That is the purpose, as pressure equalizing on the system will allow unit to start with less labor. Locked rotor amperage is four to six times that of running amps. Excess amps are always converted to heat. A loose connection will pull excess amps and could eventually burn and over heat a compressor terminal.

michaeljc70:

--- Quote from: JWWebster on July 14, 2012, 05:13:00 PM ---You might have a burnt wire on the compressor. Sometimes a brief interruption can cause a terminal wire to melt. I would check for a fail compressor capacitor. Might be that the fan motr has a sep cap or that the fan side of the cap is ok. Could be a contact on the magnetic contator has been fried.
My page: https://sites.google.com/site/sublimeappliancerepair/ask-the-sublime-one-a-question/outside-condenser-blues

--- End quote ---

After looking around on the web, I had actually taken the panel off the a/c unit and inspected the capacitor. It looked surprisingly new (unit is 11 years old). 

One thing that was a little "Burnt" was the thingy in the box on the side of my house. It is a metal electrical box and instead of a pull down handle, it has a cartridge like thing.  I pulled that out and it looked a little burnt and there was a little melted plastic on the box part.  I figured that probably isn't it as the unit has power and as I understand it, it either has power or it doesn't. 

JWWebster:
That might be a barrel fuse. Be careful with that.

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