Air Conditioner slows down and then speeds up

If you read the information on the controller for the Intellitec Climate Control for 'auto', it describes exactly what is happening. I suspect whatever your unit uses for controlling the A/C is attempting to mimic this scenario that Intellitec uses. What you are seeing is that the sensors are telling the unit that it is cool enough so it slows down, then it says it is still cool enough for awhile so it stops, then the sensors say 'too warm' and it starts up again but since it stopped, it waits two or three minutes to allow the compressor to clear itself, then starts the compressor.

The solution is to switch to 'hi cool' and see if that doesn't stop it.

I installed a new fan motor last night and that did not make a difference. I thought for sure it was the motor. So it must be the control board or the thermostat?

So I tried installing a new Fan cap and that didn't make a difference. The fan is still not coming on for any of the low settings. Time for a motor I guess.

BraxtonBaird1 wrote:
Thanks wa8yxm, I like that idea but how do I determine which plug is on the same leg as the A/C? I know for sure that when this happens the thermostat is not on Auto.

Two ways. ON a 30 amp RV, all the outlets and the A/C same leg or if plugged into 30 amps you will be close enough

ON a 50 amp RV you do it by the Cadence method

Left/right/left/right or in this case 1-2-1-2-1-2

In my Breaker box the mains are on the left and the branches out from there 1-2-1-2-1-2-1-2

On some the mains are in the middle and they may be the same as mine o r they may be 111111 mains 2222222

And then we have teh "Residential: type (Vertical rows mains at top

1 2
2 1
1 2
2 1

IS the usual configuration on those

If the A/C is a "2" look for outlets that loose power when you turn off a "2" breaker.

I always mess up more than i straighten up. Take to a electrical shop in your area. NOT CW. they will have the equipment to analyze it.

BraxtonBaird1 wrote:
I thought the cap was used only for starting the blower.

no, it's for running

I would also suggest as many have that the run cap is dying or
you may have a bad fan bearing that has partially dried out and is
causing a partial seizure. the bearing becomes tight due to no lube and
then heat generated melts some remaining grease that flows and frees the bearing. this cycle repeats until final seizure.

Once the fan motor is started by the fan capacitor, the fan will then run. IF it slows down and speeds up and sometimes stops, then the fan motor is the probable defect. BUT, I would also have a Voltmeter connected to see if the Line voltage drops and rises when this is happening. 50 amp service is not a concern. You can have LOW line voltage even on 50 amp service.

Thanks wa8yxm, I like that idea but how do I determine which plug is on the same leg as the A/C? I know for sure that when this happens the thermostat is not on Auto.

Obtain a plug in volt meter, if your RV is 50 amps make sure you plug into an outlet on teh SAME LEG (L-1 or L-2) as the A/C..

Two things other than a bad A/C can cause that

1: A thermostat set to AUTO that switches the fan from LOW to HIGH and back (or high to low and back) as the temp changes

And #1 on the suspect list is 2: Variable voltage in the campground.. I see this all the time in some places.. Fans slow down and speed up with voltage changes.

An RV A/C MUST have two Capacitors. One is FAN RUN and the other is COMPRESSOR RUN. Fan and Compressor won't start, won't run, without the respective Capacitor. Compressor MAY also have a Start Assist Kit consisting of a Capacitor and a Control of some kind for it. It seems most Coleman units do, and your Model Number indicates it does, or at least started out with it installed.

So... Compressor RUN Capacitor is a possible suspect. Also, have you cleaned he coils? And, do you have Air Baffles under the Shroud, along the edges of the Condenser Coil? Those keep hot discharge air from being pulled back into the air intake side of that coil.