New to RV lifestyle, need to know if this is normal

I've got a outback 295RE. similar to yours. this size trailer is very marginal with one AC unit. get it started in the morning and it will keep the trailer cool, but run almost constantly when temps get into the high 80's.

Don't expect it to cool the trailer down if you wait till the trailer is already in the 80's before you turn it on.

There are many things that affect the effectiveness of the A/C. since you said you are a HEVAC technician you likely have the tools needed to measure inside and out side temp's both at the air intake and outlelt (Both sides of the evaporator and condcenser) and you should know the book and be able to measure humidity as welel.. You SHOULD know more about this than I do since it's your job.

Thaqt said, there are things you might not know for this takes not a technician but an engineer (Guy who designs the system)

Things like what color is your RV.. When my wife was alive she choose the color scheme for my RV, it's dark, sucks in sun's heat like a vacuum cleaner sucks stuff... So on my 37' RV even with two 15K's it warms up a bit (Like 80 to 90 interior) in the summer. Had we gotten a lighter color we'd be better off.

and that is just one thing my Pre-Engineering study taught me. There is more.

Closing curtains, Use of Reflect-x (Silver stuff you put in windows) and so on will improve yorr life.

Also pull down the filter and make sure the air is being directed into the ducts and not into the attic. I used a roll of aluminum HVAC tape to seal up all the joints in the outlet box and the vents blow much stronger now.

AC should be able to drop 15 - 20 degrees between intake and outlet air. Start with that measurement and then go looking for the problem later. We had a Dometic 15K OEM in 2013 and a replacement Dometic 15K in 2015 that both failed due to pin hole leaks in the evaporator with loss of Freon. Had exactly the same symptoms as the OP. Replaced with a older Dometic unit made in Elkhart instead of China that is running strong with about a 15+ degree drop. While the quick cool dump will cool quicker after a hot day with no AC, if you have to park in the shade, insulate your windows, etc., then you probably just don't have enough AC capacity. Folks have commented on line that having 2 ACs helps get things cooled down quickly, sometimes allowing one of them to be turned off after that.

Use a regular thermometer and check the delta T across the coil, compare to unit specs. If it is low and you have proper air flow your refrigerant charge is probably low.

Thanks all,

I just had it professionally cleaned so that isn't the issue, and I start it up in the morning but it doesn't keep up, even with the quick cool vents open. At night and in the shade it works fine.

I have used a laser thermometer on the unit. When I tested it, I had 72 degree air coming in and 60 degree air coming out. The air coming out should be closer to 48-50 degrees. This is also considering the +/- 5 degree factor of the thermometer.

What really concerned me was when I stuck my hand in the air return (above the filter) I had uneven temperature air inside. The right side was significantly cooler than the left. I shot the laser up to the top of inside of the unit and got a temp of 67 degrees on the top right corner of the shroud and 81 on the left. And here was the really wierd thing. The sun was on the right side of the coach but the LEFT side of the shroud was hot to the touch. The right was nice and cool. Also the "GL" wire seemed to be loose. Even tapping the wire would cause the unit to shut off. Doesany of this sound normal?

I find it hard to believe a 15k BTU AC can only manage to cool my coach 3 degrees in direct sunlight.

taddyport just made me remember an event we had with our previous camper. For some reason, it quit blowing cold air, but it was blowing. If I remember right, in desperation, I posted for possible causes on these forums.

Someone suggested that maybe the fins (the thing that reminds you of a radiator inside your car) might be iced over. If the weather condition are just right, it's possible the air conditioner is kicking out so much cold, and condensation on the fins is freezing before it has a chance to evaporate. As it get's colder and colder and more and more condensation building up, the fins can actually ice over and block all (cold) air flow completely.

So I pulled the sponge air filter cover and could see the fins, and sure enough ... there was a good 1/2 inch white ice built up over the fins. The solution was to let it thaw out and melt all the ice away (which didn't take long with the heat we were experiencing).

Once all the ice was gone, the answer to keep that from ever happening again was to start the air conditioner at a higher temperature. Turn the thermostat down to where the air conditioner "just" turns on and no further. Let it cool to that point and wait for the air conditioner to turn off. Wait a minute so the air conditioner can recycle, and then turn the thermostat down, just a pinch until it turns on again.

Keep doing this until the temperature in your camper is where you want it.

If the air conditioner runs constantly for a long period of time, the ice that builds up on the fins never has a chance to melt off. The air conditioner needs to cycle on and off so warmth and evaporation will keep those fins from icing over.

After that one-time experience, I've never just turned the air conditioner thermostat on 70 degrees when the outside temperature was 90 and the inside temperature was 100. I've always brought the temperature down slow this way, and never had a problem again.

By the way, in our house, we have 2 central air conditioners. Both coolers are in the attic. A couple years ago, one of them started blowing hot heat. I remember the experience with the camper and opened up the return vent in the ceiling, looked up there and... and sure enough ... fins iced over about an inch thick! It was a fluke, but it does happen.

Not sure if this could be your problem, but it's also something worth exploring.

Another thing you may want to check is build up on the AC fins. With mine I can pull the filter off and take a flashlight and look inside at the fins. They can get a lot of dust and gunk build-up in the fins which will really restrict the airlow and in turn the efficiency of the AC. If they have a lot of build up on them then it becomes a different job. You can probably do a search on "cleaning AC unit" and have some success.

Dutchmen just covered it well, the "quick cool" ports should make a huge difference and at the least give you a very cool, comfortable main living area. If they dont then its time for a service visit.

If you are starting up the air conditioner after the inside of the camper is already hot, it may not cool very much as the heat inside is just too much. Here are a couple tips you can try to see if you can get better service out of your air conditioner before changing or doing anything.

1) Turn on the air conditioner in the morning when the inside of the camper is still cool and it will keep it cool all day. If you wait till the camper is already hot, it may never cool it. (same as with your house, start it in the morning and it will keep up. Start it after it's already hot, it too late.)

2) If you have been traveling and the inside of the camper is now hot, and you are ready to stop for the night, keep all your slides pulled in. Turn on your air conditioner, and cool the camper. A smaller space will cool faster and even if it's hot inside, the chances of cooling are greater. Once the camper is cool, then open one slide at a time time until the temperature catches up again. This may take as long as an hour or longer, depending upon how hot it is, but it will usually work.

3). Do put a thermometer at the air output points and see if the air is actually cool blowing out.

4). If your camper camper has ducted air, chances are the air conditioner also has the dump vents on the main unit. Open them all and let the air dump directly into from the air conditioner and skip the air ducts running in the ceiling. This dumps the air right into the coach without passing through hot air ducts first, which have to cool first before any cool reaches the vents. Also, if you do the AC dump with slides IN, it will cool even much faster if the coach is already hot.

If these things don't work, then you really need to find out what the actual temperature the AC is spitting out air. If it's not spitting out cooler air, there's something wrong with the air conditioner. If under warranty, talk to your dealer. If it's cooling, just not cooling the coach, then the problem is simply the space trying to be cooled and the air conditioner is just not hefty enough to over come.

Good luck.