Coleman RV Air Conditioner?

[laplatarosa]

I have a Coleman 13,500 BTU RV air conditioner that is blowing hot air. I took the shroud off, but nothing seemed out of place. It blows warm air into the MH.

Any ideas where to start trouble shooting? We're in Zion National Park and it is in the low nineties.

Unit is about 10 years old. We drive a 2006 Winnebago Sightseer 35N on a Workhorse Chassis.

We've recently been on some rough roads returning from Alaska. Have not had it on since Apr'15; when it seemed to work fine.

Thanks in advance for your help and ideas.

Laplatarosa

[laplatarosa]

Well, It is not fixed, but I have not given up yet.

With lots of help from poster J-D we tested all of the capacitors and all tested good. I even switched all the electrical parts from a working 13,500 BTU AC from the front of my coach. Still the back AC does not work.

I'm headed to AZ in the next week or so for our winter home. My rig will be undercover for most of the winter. My plan is to remove the non-working unit from the MH once in AZ. I'm hoping to find a shop that can bench test the AC to see if it might have just lost it Freon. Of course they would then have to find and fix the leak before re-charging the system.

Does anyone know of such a shop in the Mesa, Scottsdale, Gilbert, Phoenix, or Apache Junction area that you would recommend for looking at my AC?

Thanks all and specially J-D for all you help.

LaPlataRosa

[j-d]

Model Number is 8534C8764

And this is the Wiring Diagram

I confuse easily with wiring diagrams as it is, but this Heat Pump unit seems to use its Start Capacitor ONLY when the Reversing Valve is called for. And I can't tell from the diagram whether the Valve is used in Heat Mode or Cooling Mode.

Hey OP - When a unit shuts off and its reversing valve was in play, it'll often make a "sneezing" sound. Does this unit do that? Or your other one? If so, in which Mode, Heat or Cool?

We've talked off line, and you found the reverse valve disconnected from the start capacitor. It never used Heat Mode. If that's the case, bad start capacitor doesn't seem to be a possibility. Compressor Run capacitor stays on the suspect list. Do any of your meters measure Capacitance? Scales might be marked MFD or uF.

[j-d]

You don't have Private Message enabled, so you'll have to contact me. There are instructions in "Forum Tech Support" explaining how to post pictures. Basically you have to have the pix on "some" web page. Could be a photo site or your personal website if you have one. Then you use the Advanced Post Form (right above the Quick Reply window, and link the posted pic to your RV.net thread.

[j-d]

Then:

Allow 30 minutes or more for A/C to cool compressor thermal safety is closed

Turn power to A/C off at Breaker, leaving Thermostat in a setting to demand cooling.

Open the unit up to see capacitors and find a point to check voltage to compressor

With meter leads and your ears in place, have Helper turn the power on

Let us know if you have voltage, hear compressor try to start, hear internal safety click "out"

If compressor gets voltage, it doesn't start, clicks "out" and voltage then rises, let us know that

I wish we had a way to check current draw and/or test capacitors. You can at least look and see if they look bloated or fluid leaking out.

I'll send you a private message with my email ID. Send me any pix you take and I'll try to get them posted.

Find a place to check voltage

Wi

[laplatarosa]

I have a volt meter.

I do not have an amp meter with me.

I have a helper.

I will try to provide make & model number.

I do not know how to post pictures on this forum.

Thanks again,


Laplatarosa

[j-d]

When you go up there, you'll take the plastic shroud off then the cover plate noted above to look at the capacitors. If you possibly can, take pictures of the capacitors and the wiring diagram that I think you'll find just forward of the capacitors. If you can't do that, please provide the model number of the A/C, should be on or near that wiring diagram.
To determine if compressor's trying to start, one or more of the following is useful:
A volt meter
An amp meter
A helper
Got any of those? Which one(s)?

[laplatarosa]

We have wall mounted thermostat.

I cannot hear the compressor from inside the MH.

It is too hot on roof to feel if the compressor is trying to run/ getting hot.

I plan to be on the roof first thing tomorrow I'll try to check the starter.

Thanks again,

Laplatarosa

[Big_Katuna]

You need to pull the shroud off, then take off a piece of sheet metal over the part where the wires from the fan enter the ac unit. Thats where the start and run capacitors are. See if any of them look bulged out or if there are ant dead electrons laying around.

[Triker33]

Can you hear the compressor trying to start? Is the compressor getting warm/hot to the touch?

Does it have a wall thermostat? Or controls on the bottom side of it?