For the HVAC guys

[stiles watson]

My A/C trips the breaker for time to time during the hot part of the day. It seems to happen after it has run a long time and can't keep up with rising heat. Even with my second A/C unit, temperatures get up to 84 when it is 100+ outside. Is the main unit about to have trouble or do I already have trouble?

[BB_TX]

Looking forward to the answers.
We arrived at Palo Duro Canyon State Park on Thursday. Temp was about 104. Turned on both ACs. Rear tripped the 20 amp breaker after about 15 minutes. Reset it and it would only run 2-3 minutes before tripping again. Would wait 10-15 minutes and try again. Would trip after 2-3 minutes. This continued until about sundown when the outside temp started cooling down. Then it ran fine all night.
Next day it was very hot again, but it only tripped one time.
Today in Raton, much cooler (mid 80's) and it never tripped.

[scductman]

Stiles mine did that when it was only about 1 yr old. if the breaker has tripped several times it will not hold as much amps. I changed mine for a new one and never had another problem. JMHO
Bobby

[ole dude]

If'n you have an amp meter and if you know the rated load amps of your a/c unit,and have the proper voltage, you could know by measuring the amps if the unit is over amping. Providing that the power supply is sufficient and you are not over amping, then it is doubtful of unit problems. Bobbie's tip, may be the solution. Many times the agency that rates these units does so based on 95 deg outdoor temp and 75 deg indoor temp. When you fall out of those parameters, things can go awry. When the temps get into the range of over 100 deg and are out of design parameters the head pressure gets up there real high causing the compressor to work much harder to pump against the higher pressure and the unit will pull ampheres beyond rated amps causing the breaker to do its job and trip. No solution, just information. Although not practical and in many places forbidden, a water sprinkler on the roof would do wonders, just sayin.

[HOOK]

Circuit breakers are not expensive. Replace it just for peace of mind. If problem continues take further steps.

[Ozz]

Good advice, breaker tripping on A/C units can be as simple as a bad breaker, but usually it is loose wiring at the breaker connection, possibly downstream at the unit itself.
High head pressure tripping closely matches the symptoms you describe, Cottonwood seeds in the air where you are? The single most occurring culprit. Check the coil on the roof, see if it looks obstructed. These units are designed to run in very hot weather and stay on, but all conditions have to be right. I think your unit is fine, as it runs for some time when loaded up.

[stiles watson]

Note to self: Clean coils on roof and change out breaker.

[Bill-N-Donna]

I just went through the same thing recently. I had the coils cleaned really well. It seemed to run better but I had to get the HVAC guy back over to look at it and his recommendation was to replace the unit. I suspect that ours was used on a full time bases before we got it. I use it a lot even when we’re not camping so I think 10 years was good service from it. The new one is doing much better!