Coleman Mach III Air Conditioner - Page 6 - Answered Questions & Fixed issues

There should be an overload protection device in series with the low voltage wiring(t-stat wiring) Is it resting on the heat strip or too close to it? It is a saftey device to shut off the heat strips if the fan quits or a fire in the heat strip section. check that or by pass it, if it stays running then ur thermal protector is bad, couple bucks at the parts house.

I think it is the thermostat problem.

Hi, yes you can use the same thermostat if you are replacing the unit that has the same sequence of operation. What I mean is, if the old unit is a gas fired furnace and outdoor condenser split system for the a/c you can use the same controls, or if its a package unit. Now, if you are installing a heat-pump unit in place of a gas fired central unit, you will need to pull more stat wire and buy a heat-pump thermostat to make it run.
Shastalaker7
A/C, Heating Contractor

Where do you live. A zip code is best. As long as you know the parts you need and your not going to ask how to repair your unit, parts are easy to come by. Give me your zip and I'll give you a dealer.

Most rooftop RV units do not have service ports installed. You would have to get line tap valves to install in the system. The next problem would be getting some R22. Unless you have and EPA CFC certification you cannot buy R22.

Hi, I would have to say you have R-22 in this system. 134-a is for autos and some refrigeration commercial units. R-410-a is for the new residential units. and is a very high pressure freon. So, yes yours is R-22.
Sincerely,
Shastalaker7
A/C, Heating,

Hi, and the answer is no. This system is a sealed hermetic a/c unit, and does not require you to charge the unit, only if it develops a leak in a coil, copper line, or a line has rubbed through causing it to leak. If it is cooling good, your freon level should be fine. It doesn't hurt to go on top in the summer or before it gets hot, remove the cover and take your garden hose and kill power. Now, wash the coil out real good. They get very dirty and cause the pressures in the system to get real high and the unit will not cool like it should. This is about all you can do, but its very important. Keeping the indoor filter foam clean is also good, but no you don't need to charge it on a regular basis, only if you have a leak in the unit. Please don't forget to rate me as I know you will be kind. Please let me know if you have any problems with your unit, and I will be happy to help you out.
Sincerely,
Shastalaker7
A/C, Heating,

Hi, this one will be difficult to trouble shoot with out being there, but there are some things you can check. You say there is voltage to the thermostat? This sounds like a power problem, or the unit is off on a safety. You have power going to both the unit on top and the indoor unit? I believe this is what you are saying. When this unit was removed, was any freon lost that you know of? If the unit on top was not pumped down which I believe on this kind of system, they are not set up with a pump down valve to pump the freon from the outdoor unit to the outdoor receiver unit so the top unit can be removed, the problem is its off on its low pressure switch because it has no freon in the system at all. The freon has to be recovered to remove the condenser from the roof, and when installed on your roof, it has to be evacuated with a pump and recharged. If it has pump down valves on the high side line, this valve has to be closed off while the unit is running, and the compressor will pump the freon into the condensers receiver. After it is connected to your indoor coil, it has to be evacuated and the freon has to be released by opening up the liquid line valve to let the freon go through the system. Both the indoor and outdoor lines ( freon lines ) have to be connected and the air has to be removed by a vac. pump to make sure all air and non-condensables are removed before the freon is let loose or it is charged to spec's. Don't worry about the run capacitor. I strongly believe this unit has not a drop of freon in it and I don't believe it has a pump down valve on the compressor, so the last owner either bled the freon into the air, or it has a valve on the compressor that you can look for on the smaller of the 2 copper lines. If there is, you should have the unit evacuated before you open this valve. If you want to open it and take a chance on it, turn the valve in like you are closing it, its the opposite of a water valve and the unit will start if there is freon in it. You may want to call this guy to see what he did and if he did pump it down to save the freon. It has to go somewhere when the unit is split apart. I hope the best for you, but this is the problem, it will not come on due to no freon or its in the receiver. Call him and find out what he did. Please let me know what you find out. Please rate me as I know you will be kind, and I will be here to help in any way I can. Keep me posted on this.
Sincerely,
Shastalaker7
A/C, Heating, & Refrigeration Contractor

if it is a programmable thermostat you can unhook thermostat and when it comes on select 3 instead of 1. As it sounds as though it is short cycling this happens in older houses with drafts. Hope this helps Tim

Hi,
Yes, the capacitor to the compressor or the compressor its self have gone bad...try changing the cap first....then if that don't work its big bucks...

heatman101

Try a new fan motor. It runs about $125.00, It will run a few min. then will trip the motor themal switch. you can probably still here the compressor running. It may also trip the breaker on shore power . good luck! the part you are looking for is a 1/3 hp 115vac 2 speed 1580/1020 rpm part number #1468-3069

Sounds like the contactor that controls the compressor and fan is sticking. You will have to remove the top cover to get to it. It will probably be in a box after you remove the cover. Turn the power off and see if it is still pulled in. If you can get it unstuck then it may work, otherwise you will need a new one.

Hi,

There is a wealth of information including installation, operating and technical literature available for this and other RV units at this link.

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

Please do leave a vote for the solution. Thanks.

the bearings are replaceable on some motors.. its a bit of work and you might first check the cost of a replacement motor .. it might be low enough to offset the amount of labor required to replace the bearing .. around here we have a hardware store that has a stock of most common replacement bearings ... some motors have welded bearing cages or bent metal captures .. those are harder to deal with. a way to make at least temporary repairs of such bearings involves punching the bearing to expand it , then re-drilling the bore to the correct size .. you might be able to force grease in the bearing for now to give you a little more time .. as it is it will eventually damage the motor shaft such that bearing replacement will not be reasonable ..

Hi,
The compressor is not always starting...sometimes it tries but does not start...
It could be a capacitor and relay problem... or the compressor could be going bad...
Change the capacitor and start relay first and then see if that gets it going...

Here is a tip about trouble shooting your air conditioner...

Air Conditioner Trouble -Review the Possibilities
http://www.fixya.com/support/r3571569-air_conditioner_trouble_review_the_possi

heatman101

17 ounces of R-22

Either you need to replace the square gasket between the ac and the roof or you need to seal/replace your roof..

R-22

COLEMAN R.V. AIR CONDITIONER SERVICE AND REPAIR QUESTIONS
COLEMAN R.V. PRODUCTS
GO TO rvcomfort.com
Click on RVP (RV PRODUCTS)
Click on type of AC, if you can’t find the information you want there,
then click on contact us on the Green Bar.
You can get Service Support or Email address and Phone numbers.

COLEMAN R.V. PRODUCTS
GO TO rvcomfort.com
Click on RVP (RV PRODUCTS)
Click on type of AC, if you can’t find the information you want there,
then click on contact us on the Green Bar.
You can get Service Support or Email address and Phone numbers.