Coleman Roof AC

Fellow RVers, we need help, let?s talk AC units. We are first time travel trailer owners, our Rockwood Geo Pro was purchased new last September. We camped all winter and while there was definitely a learning curve, we never had any actual problems. That is until Memorial Day. We got set up and went to turn on the AC and it wasn?t working properly. It?s still blowing cool air, but not cold at all. The trip was 10 days and we never got the temperature inside below 84 even at night and highs were only in the low 90s. We took it into the service center and they told us we just got a bad unit, no big deal, covered under warranty and after two visits to the customer service center we had a brand new Coleman AC unit. Flash forward to the next trip and imagine our shock (and frustration) when after hooking up at our next incredible campsite we noticed we still had the exact same problem. We took it to the service center for a third time and after spending all day at the service center we were told we must have ?been unfortunate enough to get two bum units in a row.? They ordered a new unit and will be installing it next weekend. I can?t help but think about the definition of insanity and I have no faith that this will actually fix the problem. We have no choice but continue to use this service center due to the warranty and are extremely frustrated with all of the perfect camping weekends that are slipping by while we deal with this. Have any of you ever dealt with this? Or heard of a similar problem? Is there anything you can think of we can try or have them check? Any and all suggestions are greatly appreciated!

Coleman has been building roof AC units for a long time, and it's highly unlikely that you've had two bad units on a new RV. It doesn't sound like the shop did much, if any, troubleshooting. A single AC unit can struggle to get an RV cool, especially in the hot sun, but here's what I'd check... Take a look at the thermostat and make sure it's set to Cool, not just Fan. Is the desired temp set correctly? Can your hear the compressor cycling? In humid conditions, AC units can ice up and stop blowing cold air. Just some things to consider.

Kev

One issue is that people expect too much from an RV A/C (or a home A/C for that matter)

First though. go up and inspect the condenser coils (The otherside coils) on colemans air is sucked in through the condener if the condener is clogged then it does not work as well (or at all) since it can not suck air. 4 screws, remove the cover. peal the thing clear. replace cover and screw  Easiest A/C to clean on the market.

At best you can expect about 20 Degrees drop between intake and outflow.  Use a Thermomemter (Probe type like a meat or A/C test thermometer to measure temps.

If it's very very hot and sunny out performance ... Suffers.

Thank you for the suggestions! All of the settings are correct and were checked hundreds of times during both trips. I should have mentioned, our TT is small - only 20ft and last summer the AC could turn it into an ice box so I don?t think it?s struggling because of one AC. I can hear the condenser cut on when it is changed from fan to cool but I will definitely check if it needs to be cleaned!

Sadly, few RV shops have any techs who know much about a/c other than how to replace the rooftop unit.  The chances that you got one bad unit, let alone two, are infinitesimal.

Since you had a complete replacement a/c with no improvement, I think we can rule out dirty condensor coils as the cause. The entire condensor got replaced and I think we can assume the new unit wasn't already dirty.

You hear compressor cycling even though the interior hasn't cooled to the thermostat temperature? That's not right - it should stay on continuously. However, the a/c will shut its compressor down if it senses some abnormal conditions, e.g. a "freeze-up" on the evaporator (heat exchanger) or excessive internal pressure.  A freeze condition usually indicates an air flow problem, while high pressure is a more complex thing and harder to pin down.

QUESTION: Does this a/c have ducted outlets and a wall-mounted thermostat? Or is it a self-contained unit with the controls and thermostat right on the ceiling unit?

There have been many investigative reports on the news of car mechanics not touching a thing when a car is brought in for service. I would look for a serial number on the top unit then take a picture of it. Or just make a small dot with a black magic marker where it is inconspicuous. If you have it replaced again and it still doesn't work make sure it they actually replaced it.

I definitely have wondered if they actually replaced it, the only proof I have that they did is the AC manual they left inside the RV and some dirty fingerprints on the white panel on the inside of the RV. I have noted the serial number of the current unit so I can check next time.

The unit is self contained and the controls are right on the unit. When I say I can hear the condenser, I guess I should clarify since that is what the RV tech told me I was hearing, perhaps he was mistaken. To turn on the AC you have to turn the dial past low fan and high fan before getting to the low cool and high cool options. When it clicks from fan to cool I can hear a humming and that something clicked on. There is a distinct different sound from fan to cool. I was told that is the condenser. The other dial is always turned to the biggest blue part. (We even tried changing it to the red just to see if maybe something was put on backwards, but that didn't work.)

Ah Same controls I have. The Coleman compressor is not very loud  An easy way to see if it's running is to put a clamp on AC or AC/DC ammeter over the wire coming off the A/C breaker.. (NOTE dangerous voltages inside box be careful..  As I recall a 15000 BTU coleman is 13.9 amps compressor running. IF you can not personally watch the meter you will see the blower come on at just a little current. then 13 or 14 when compressor kicks in (Or 13.x may not be 13.9 but 13.anything works)

I"m not sure the draw on a 13500 btu

As the world gets hotter. A/C's work harder and eventually can't keep up

There is no frost sensor on that model or so Coleman tells me.

My experience has been that when the Temperature outside is over 95 degrees and the humidity is high (hazy skies and hard to see the clouds on a sunny day) that a camper setting in the afternnon sun can only cool at the most 12 to 20 degrees from the outside temperatures!
Just my observations others may vary!