Ac loses power after some time. please help

[tsubeta04]

Yesterday evening we started having problems with the ac after turning on the water heater. Not sure if that has anything to do with it.

We noticed it sounded weak so we turned it off, changed settings several times, cleaned the filter, reset the breakers and nothing worked. It wasn't until I disconnected and reconnected the shore power we are hooked up to that the full power of the ac came on. The compressor also started to blow out cold air. Then it happened again in the middle of the night and this morning. It'll work temporarily only if we reconnect the shore power we are hooked up to.

Any ideas? The door containing all the fuse information doesn't list what electrical device the fuse corresponds to but the sticker next to the ac unit says that it requires 20 amp. I checked the 20 amp fuses but they all look fine.

We are located in Santa Fe, NM and will continue on through several states more after this with high altitude. Not sure if that's a problem.

We would really appreciate any helpful info.

 

[Dakota 1120]

Perhaps the problem is in the shore power box and not in your unit ??

Did you have campground maintenance check the power output of the shore power box?

 

[brackenlip]

Sounds like low voltage ( brown-out ) at the campground pedestal. This is very hard on your equipment, such as your air conditioner.

This is one reason why I use a "surge gard" as these devices protect you from low voltage, by disconnecting you if the voltage goes too low.

If you have a voltmeter and know how to use it, I would check the voltage ASAP.

 

[Dakota 1120]

Yes, Surge Guard is great ~ I have/use this one~ purchased 'elsewhere' for much less. Shop around.

https://www.amazon.com/Technology-R...465514521&sr=8-4&keywords=rv+surge+protectors

Here is a great comparison listing of surge guards:

https://www.rvupgradestore.com/Articles.asp?ID=279

 

[runner421]

So-I'm guessing you're at a location that's providing a 30-Amp hookup. Sometimes, with "dirty" power, when you're sucking major power involving two big things: A/C & Microwave, A/C & water heater, Microwave & water heater, etc. You get the idea. . .
What COULD be happening is that at first the A/C fan starts, then the compressor. Compressor shuts off when desired temp is reached. Fan blows a while longer (unless you've got the fan set to always run) then shuts off. The next time it kicks back on, it may not have enough power to start the A/C's motor. So it can lock up and/or shut down the capacitor.
I had a similar problem, there's a modification available (especially helpful if you run your camper on a generator). Replace the stock capacitor with a Hard Start Capacitor. I've tried A/C with a 20-Amp connection, from my solar power (batteries)-the hard start capacitor has solved my situation.
What could be happening is that by disconnecting from shore power and reconnecting you are letting pressures within the A/C system equalize and then compressor motor starts when you try again.
Check out this link - talks about generator and altitude, but could be applied to dirty power, or if you're hooked to a 30-Amp source but getting less?
RV Air Conditioner Hard Start Capacitor | ModMyRV

 

[tsubeta04]

The responses are much appreciated. Turns out it was a much easier fix than expected. It wasn't making sense to me once disconnecting wasn't working anymore so I removed the filter cover to reveal frozen coils. Ran the fan on high for a minute and opened up all the windows. Once the ice melted off the ac has been fine since.

What I think was happening was that when we disconnected it gave the ice a chance to melt and thus would work until the ice built up again.

We were freaking out; New Mexico is our first state in an 8 state trek this summer and the thought of a major repair had us stressed out.

Thanks again,

 

[APD]

Keep an eye on it.
If the indoor coil is regularly freezing your troubles may not be over.
The indoor coils will freeze for only two reasons, low air flow or loss of refrigerant.
Assuming your coil and filter are clean:
If you like it really cold inside, and normally run the temp control to the lowest setting and the fan speed to low, you might try raising the temperature setting slightly and increasing the fan speed for a similar effect. If it still freezes you may have a refrigerant leak causing low pressure and resulting coil freeze up.
Hopefully it's the airflow issue and not a leak. Refrigerant leaks can be expensive to locate and repair.