AC not cooling down

[PCIowa]

We purchased a used 2017 Keystone Hideout 299RLDS from a local Keystone dealer. It is plugged into a 30 amp service (30 amp camper). Turned the AC on last night when we got it home. It’s still 83 degrees in the camper. It won’t cool off. Has anyone else had this problem. Or any suggestions. Thank you!

[JRTJH]

Can you feel any air blowing from the discharge vents? If you plugged it in yesterday and it was running on low or if the humidity is very high, it may have frozen up, preventing any air flow and stopping all cooling.

[PCIowa]

Yes there is air coming out of AC vents. We put a thermometer in one of the vents, it reads 55 degrees. We have it on high. And yes, the humidity is very high here in Iowa right now. Thank you.

[JRTJH]

Maybe it's something with the thermostat? You can move the set temperature up and down and see if you hear the air conditioner compressor "click on" ???

If you can you hear the compressor turning on, does it sound like it's laboring or does it just "sound like it's spinning under no load" ??? If you can't hear the compressor laboring, the A/C may have leaked Freon and no longer be cooling ??? Just a guess, but if you have a line ammeter, you can get on top of the RV and check the amperage at the compressor. If it's too low, no Freon, if it's too high, a locked (defective) compressor.

Unfortunately, RV air conditioners are, for the most part, not repairable, so it's get it checked and likely you'll need to buy a new one.

[sourdough]

It's "still" 83 inside; what's the temp outside? If you're getting 55 at the vents it sounds like you're in good shape since you have good airflow. That's a 32' 5th wheel and if it's hot and humid outside with a 13.5k AC, I'm not sure anything is wrong other than needing a 2nd AC.

Edit: If you're dealing with high humidity daily we found that a dehumidifier really helped (along with the 2nd AC).

[travelin texans]

You could remove the inside cover & check the gasket between the output & return air plenum is in place.
These things are poorly insulated boxes, regardless if they call them 4 season or any other cute name, and a rv the size of yours, 30'+, with only one ac will probably never do much better than that in extreme heat. Place a couple fans around to move what little cool air there is will be about your only option & try to park in the shade if possible.

[Customer1]

Don't expect one A/C unit to cool a 30' trailer on a hot day. If you've got 55 degree air coming out of the vents, your system is working fine.

[Canonman]

Do you have the "Quick Cool" dump vents open??
These are the big vents that will dump the most cold air flow directly into the main room under the A/C unit.

[kfxgreenie]

Originally Posted by PCIowa

Yes there is air coming out of AC vents. We put a thermometer in one of the vents, it reads 55 degrees. We have it on high. And yes, the humidity is very high here in Iowa right now. Thank you.

Wasn't it nearly 100 degrees with a heat index of 110+ because of the humidity? That A/C was working hard depending on if it was in the sun or shade it might have been giving all it had and that was it.

[LHaven]

Originally Posted by JRTJH

Unfortunately, RV air conditioners are, for the most part, not repairable, so it's get it checked and likely you'll need to buy a new one.

On my last rig, my A/C started getting warmer at age 19. The manufacturer advised us not to have it recharged, but wouldn't tell us why other than to repeat the advice. I had a local HVAC pro install charging taps in the coolant system and perform a recharge, and the unit operated like new for the final two years we had it, so at least that much can be done if you find the right pro.

I agree with the others who are saying that 55° air at the vent indicates the A/C is cooling like it should. Next things to check are air distribution, outdoor temperature, and sun impingement.

[JRTJH]

I completely missed the statement, "We put a thermometer in one of the vents, it reads 55 degrees."...

With that statement, I agree, it looks like the air conditioner is working (25-35F drop from ambient temp).

There may be some cooling loss from leaking ductwork/vent openings. Maybe you could obtain a bit better cooling by checking and resealing any leaking vents or ducts. Be sure to check the "cardboard/foam" separator between the warm air return and the cold air supply in the overhead unit. Often there is some leakage and the cold air gets "sucked back into the return duct".

With outside temperatures over about 90 or 95F and the trailer sitting in the sun or only in partial shade, I agree with the others. Keeping the trailer interior in the low 80's may be the best a single A/C can do for a trailer that size.

[PCIowa]

Thanks everyone for the info and comments. I contacted the R.V. dealer we purchased it from and we will be taking it back Monday for them to figure out.

[chuckster57]

Originally Posted by PCIowa

Thanks everyone for the info and comments. I contacted the R.V. dealer we purchased it from and we will be taking it back Monday for them to figure out.

Are you able to perform any of the checks mentioned? I’m only asking because I think your going to spend money that you don’t need to.

[Roscommon48]

did i miss where you are located? you have a 13.5Kbtu...if you are in a humid hot area....good luck on dropping your temp.
best but would be to get in shade and add another A/C...sorry, that is the world of most rvs.

[jack.knight]

I had the same problem last weekend when the temp reached 100 here in New England. couldn't get the AC below 84 degrees. While diagnosing I held a napkin up to the exhaust port and notice the air was being sucked into the unit and when held to the intake (where the filters are) air was being blown out. There was no airflow out the ceiling register in the bedroom. I thought the fans were running backward so I tried switching from the 50 amp to 30 amp on the power pole. Same issue and I realized that if the power was wired wrong at the poles then the fridge and condenser on the AC wouldn't work. I found a camper with the same (Coleman) AC I found some posts about the baffle being installed wrong at the factory then warm air would leak with the cold. Long story still long. I took off the bezel to check the baffle and saw the piece under the bezel was installed backwards so the exhaust (cold air) was being diverted to the intake filters and the intake (should be warm air) was blowing out the cool air. total time to fix 15 minutes and six screws. Total time to figure it out, a day and a half.

[bbells]

Check the voltage in your outlets when the AC is on. Mine did the same thing when I used an extension cord from my barn. The power was 115 with the AC off, when it switched on it dropped to about 1oo. The AC would blow cool air for a minute or two, then it would stop, but the fan would continue to blow.

[LewisB]

We live in Tucson where the ambient temperature can commonly reach or exceed 110F. When "starting hot", we've never had a trailer that could get comfortable with 1 or even 2 AC units. If the inside temperature is 90F when you start up the AC system, the "mass" of everything inside the trailer needs to be cooled along with the air. Furniture, cabinets, walls, floors - everything is staring at 90F and will need to be cooled before you see much drop in the inside air temperature.

So, when possible, get your AC unit(s) running early in the morning when the mass temperature inside the trailer might be (say) 75F. Now, your AC isn't trying to cool down all the internal components along with the inside air. You will have a much easier time "maintaining" a cooler temperature rather than "dropping" the temperature.

Our most recent trailer has 3 AC units! The only way to go if you live in hot country!

[vulcanwayne]

Had a similar problem with my unit and dealer sold me a second ac. After getting back home. I investigated further. My problem originally was insufficient airflow from the duct system. I removed the 6 screws from the ac cover and looked in the airflow box with my phone camera only to discover that the corners were not sealed and allowing a significant amount of air to escape into the ceiling. In addition one of the ducts was misinstalled with approximately 70% of its airflow blocked off. After returning it to the dealer for repairs it is working great and so far we have not turned on the second ac unit!

[3snowbird]

RV airconditioners will only cool 20% so depending on the outside temp will determine the max inside temp

[itat]

This video may help.

https://m.youtube.com/watch?v=rxCljBVi8DU