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Doug Miller

In article .com, wrote:
On 5 Jun, 20:39, (Doug Miller) wrote:
In article . com,
wrote:
I am running my window air conditioner on a 20 amp line run directly
to the breaker box. It runs fine for quite a while, through numerous
cycles, thentripsthecircuitwhen restarting itself. I am not very
knowlefdgeable in AC, but it seems to me the thermostat is shutting
off the compressor and trying to turn it back on too soon (about a
minute). Does this sound like a defective thermostat or is some other
circuitry involved?

Sounds to me more like the A/C has been loading thecircuittoo much for too
long, and causing the breaker to trip from overload.

What is the amperage rating on the nameplate of the A/C ?

It only requires 15 amps.

Well, you're getting close to the maximum continuous load allowed by the
electrical code on a 20A circuit. (Continuous load is defined as maximum
current for three hours or more, and is limited by Code to 80% of the
circuit's rating, or 16A in this case.)

I think the first thing I'd try is a new 20A circuit breaker. They're cheap,
and they do wear out -- particularly if they are repeatedly loaded heavily
enough to make them trip. DO NOT even think about replacing the 20A breaker
with a 30A or higher unit. That is a serious fire hazard.

With the breaker OFF, check the connections at the receptacle and at the
breaker. Make sure they're snug, with no evidence of corrosion. Replace any
corroded parts.

Take the A/C unit cover off, and clean it inside. A buildup of dust and crud
on the blower can cause it to work harder and draw more current than it's
supposed to.

If none of that takes care of the problem, it might be time to rewire the
circuit with #10 copper wire and use a 30A breaker. DO NOT use a 30A breaker
on your existing wiring. It isn't safe.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.