Air conditioner service

[DennisB]

Hi-our 2020 2720 trailmanor has an air conditioner that sporadically fails to blow cold air. I would like to do maintenance on it. Can I climb up and walk on the roof without causing damage.? We are full time in it and really don’t want to close it down. Can it be worked on from underneath? I have cleaned the filters but haven’t gone any further. It is a Coleman Mach air conditioner.

Thanks for any input
Dennis

[Wavery]

Originally Posted by DennisB

Hi-our 2020 2720 trailmanor has an air conditioner that sporadically fails to blow cold air. I would like to do maintenance on it. Can I climb up and walk on the roof without causing damage.? We are full time in it and really don’t want to close it down. Can it be worked on from underneath? I have cleaned the filters but haven’t gone any further. It is a Coleman Mach air conditioner.

Thanks for any input
Dennis

Absolutely do not walk on the roof, especially when set up (unless you weigh like 50#).

There isn't a lot to be serviced up there other than cleaning. If you want, you can get some A/C coil cleaner at Home Depot. Remove the cover, vacuum out all debris, hose the inside off with a garden hose. Spray some coil cleaner on the coils and rinse it off.

You can do this with a tall ladder. If you must get on the roof, put the roofs down, put a 2x4 on each edge of the roof then put a 2'x8' sheet of plywood across the roof to sit on. The roof is arched with the middle being higher than the sides, that why the 2x4s on the sides, to make the plywood level. This will spread your weight but you still need to tread lightly. If you are over 200# (like me), you may want someone else to go the plywood for you.

Most of the time that an A/C stops cooling, it's because of lack of airflow. You said that you cleaned the inside filters. That's good but if you still have an issue, run your fan speed at maximum only. When the airflow is slower, it allows ice to form on the evaporative coils. Eventually, the coils will freeze solid and not let any air pass. After the ice melts, the air will pass again until it freezes up again. The higher the fan speed, the less this is likely to happen.

[DennisB]

Thanks for the reply..just climbed up on the ladder…thru the vents on the cover, I could see finned metal pieces..are these the coils? Can I remove the cover without getting on the roof? How about a leaf blower to blow debris out? Also, I reset the air conditioner by turning it off and then shutting the power off to the unit at the panel-
Waited a few minutes-it worked properly when I turned it back on….also, when you say run fan speed at maximum, do you mean the “fan “ mode without the air on or the air on at high speed?

Thank you for any information-I appreciate you taking the time..

[Wavery]

Originally Posted by DennisB

Thanks for the reply..just climbed up on the ladder…thru the vents on the cover, I could see finned metal pieces..are these the coils? Can I remove the cover without getting on the roof? How about a leaf blower to blow debris out? Also, I reset the air conditioner by turning it off and then shutting the power off to the unit at the panel-
Waited a few minutes-it worked properly when I turned it back on….also, when you say run fan speed at maximum, do you mean the “fan “ mode without the air on or the air on at high speed?

Thank you for any information-I appreciate you taking the time..

Yes...... those finned metal things are the coils.

There are 4, #3 Philips screws on top of the white plastic shroud. Take those screws out and lift the shroud off (sorta wiggle it around while lifting). I can lift mine off from a ladder but I'm tall and have long arms. You can put a moving blanket down an lean on that, Just not your full weight. If you have a 10' step ladder, that would be best. Putting an extension ladder against the roof while lifted could be iffy.

A leaf blower won't do much with the shroud on. Best to take off the shroud for cleaning. With the shroud off, a leaf blower could work to remove debris. However, it won't clean the corrosion off of the coils. You'll need A/C coil cleaner for that.

If you don't want to hose it off, you can get this stuff:

https://www.amazon.com/3X-Chemistry-...634958136&th=1

[Bill]

I agree with Wavery that you shouldn't get onto the roof when the trailer is open. However, while it is closed, you may need to get up there (carefully) in order to work on the air conditioner or to do caulking and sealing as needed.

I have gotten up there by getting two pieces of 1/4" plywood or Masonite, each about 2 feet square. They are a bit flexible, enabling them to conform to the roof shape and distribute your weight. Carry your weight on one, and when you have to move, pre-position the second one and move directly to it. Avoid putting your weight down on the bare roof at any time.

I also suggest getting a plastic basket or bucket, and keeping your tools in that as you work. No heavy steel or sharp edges directly on the roof.

Finally, as Wavery suggested, you start by removing the three or four large Phillips screws that hold the shroud in place. When it is time to replace those screws, I suggest putting a drop of blue Loc-tite (not red Loc-Tite!) on each one before snugging it down. Those screws have a habit of working themselves loose as you travel. During your travels. you've probably seen a shroud lying in a ditch somewhere, bashed and broken. You would be surprised at how expensive they are to replace.

Being a belt-and-suspenders guy, after I used the Loc-Tite, I grabbed a Sharpie and wrote "LOCTITE" on the top of the (white) shroud, with long arrows pointing to the screws. If I ever have to remove them again, I won't have to wonder why they are so darned tight!

Bill

[Shane826]

If it wasn’t blowing cold air and then started working properly immediately after cycling power, I don’t think it’s a dirty coils/airflow issue. Sounds electrical. Could be a failing start capacitor or run capacitor, or the 15 year old compressor is compressing its last compresses.

If you can get the shroud off the capacitors are easy enough to change but don’t touch them until you’ve read how to do it or you could get a nasty shock even if the trailer is unplugged.

If the compressor is in fact on its way out you’re looking at a new A/C unit.

[Wavery]

Shane is right. Even if the Start Capacitor isn't the current problem, it soon will be and installing a new one may extend the life of the compressor. I always keep a spare in our trailer. I've changed a number of these at campgrounds for others, over the years. I could only do it because I always keep one on hand. When I get home, I order another one immediately.

BTW....... because this capacitor works on AC (alternating current), it doesn't matter which wire (from the capacitor) goes onto which connector that you remove from the old terminals. There is no positive and negative wire.

https://www.amazon.com/AMI-PARTS-Cap...s%2C181&sr=8-8

[DennisB]

Hi-thank you all for your replies...actually, I seem to have solved the problem..I turned off the unit and then turned off the power at the fuse box and let it sit for several minutes.
Turned the power at the breaker box and then turned the unit back on-it has worked fine for a few days now—seems like a happy ending.

Thanks again,
Dennis

[Wavery]

Originally Posted by DennisB

Hi-thank you all for your replies...actually, I seem to have solved the problem..I turned off the unit and then turned off the power at the fuse box and let it sit for several minutes.
Turned the power at the breaker box and then turned the unit back on-it has worked fine for a few days now—seems like a happy ending.

Thanks again,
Dennis

Trust me on this one Dennis......... get the capacitor mentioned above and stick it in your toolbox or something. It's $12. The next time that this issue occurs, you'll thank me.

[Shane826]

^ Yep what he said. ^