20 Most Recent Coleman Mach III Air Conditioner - Page 5 Questions & Answers

Check the temperature of the air coming out the vent If it's more than 10 degrees below the air going in it's ok. If it's the same temperature, the condensing system may be not working. The compressor may just be a quiet one!

bad motor windings.replace the motor

It's the mode switch contactors for the high setting just overview the wiring of the high cool or high fan contactors if it's not there check all leads for the high fan or high cool circuitry.

Double check voltage to unit is within specs 115-120. If motor won't start and run on it's own, a capacitor may be faulty, but if you turn it by hand quick to start it and it runs slow, and heats up, and all else checks out, I'd replace the motor. Here's a link to service manuals etc that may help you diagnose as well. ( http://www.rvcomfort.com/rvp/tech_info/manuals.php )

Get a vacuum cleaner and **** any dirt from the end of the drain hose. If you can access under the evaporator from the side, clean the base tray as well.

probably (90 %) the compressor's bad, depnding on the repair cost you probbly want to just get another AC unit

Hi, I don't know if you are still having a problem, but it sound like the flame sensor on the unit is dirty and need to be cleaned. If it has a automatic pilot, it will have a flame sensor. Its made of porcelin with a metal rod coming out the end, laying next to the pilot flame. Just 1 screw holds it in place. Remove it and clean the tip with steel wool or a piece of sanding cloth. If you don't have this set up, I would need more info on the unit, model and serial number. You may also have a faulty thermostat, but I do believe it is a flame sensor.Shastalaker7

Check blower is blowing air. If not replace capacitor or blower motor.

Check here for your model.

http://www.rvcomfort.com/rvp/tech_info/manuals.php

They would normally have replacements at any RV sales/service place, and I believe you probably have quite a few in your area. Quite often they have used ones as well, which may be a little cheaper.

Either with a ladder and shop vac and long extensions and soft brush attachment from inside with flashlight for better view, or remove plastic cover on roof and then remove metal cover over evaporator by removing the short philips screws that hold it on.

The model number of you upper unit which can be seen from inside on bottom of unit behind filter etc at ceiling, will give enough info for replacement fan. Here's a good spot to find part #'s etc for your unit.http://www.rvcomfort.com/rvp/tech_info/manuals.php

I either do it with a shop vac with a ladder and long extensions on vacuum and a soft brush attachment from inside (and flashlight to see good) or remove all short philips screws on metal cover above evaporator and remove cover to access easier.