A/C not up to par for 31sqb Cougar

[JetMek]

I've had miserable experiences with my 2011 Cougar 31sqb due to the lack of cooling from our a/c unit. The dealer replaced it last year and it still can't keep the trailer cool, the dealer pretty much gave up. I'm wondering if anbody else has this problem..? I live in south west Michigan so the humidity levels get up there but all the campers around us don't have the same problem.

[SAD]

Define what you mean by not up to par. What's outside air temperature. What interior temp does it maintain?

[byrdr1]

dual AC..
15k ducted in living area,13.5k straight blow in 5er bedroom.
last year we were able to keep the whole camper in the lower 70's in full sun at Myrtle Beach, SC.
slept under a blanket in the bedroom the first night or two until I figured out the tempature range of the bedroom unit.
randy

[KanTC]

JetMek,

Given the fact that it's a 36 ft long trailer, with a single A/C unit, it wouldn't be unusual for the A/C to be
'sub-par' in hot/humid weather. If you have 50 amp service, a 2nd A/C unit would be the best remedy.

One other thing to consider... did the dealer check the ducts/ductwork to ensure that the cool air
isn't escaping into the area above the ceiling?

Sorry about your A/C issues, but welcome to the forum.

Terri, the co-pilot :)

[JetMek]

This is a 30 amp service camper with one A/C unit. I'm not sure if the dealer checked all the duct work but I'll be sure to have them do it because it's going back to them. There is all types of campers around us with 30 amp service and same BTU ratings that do not have this problem so to me it's unacceptable. We love the camper itself but are struggling to recommend it to anyone due the A/C issue.

[JetMek]

It will not keep the 20 degree drop in temperature from outside temp to inside temp as published. It was 90 degrees outside and I couldn't get the inside temp below 80-82 while my neighbor campers were in their cozy 70-72 campers. I need to know if this is a 31sqb issue or a Keystone wide issue..?

[Terrydactile]

As mentioned before, I found all of my duct work in terrible condition right from the factory. I pulled all of the registers and taped up the joints. I could not believe how sloppy the workmanship was. There were holes big enough for my to stick five fingers through. Also the ends of the ducts were tapped with some kind of cheap tape that had come loose. I fixed those by fitting a piece of foam pipe insulation up through the last register in the run and wedged it into place. It made a tremendous amount of difference. I would estimate that 1/3 to 1/2 of my cool air was going into the space between the ceiling and roof.

Hope you get this fixed.

[JetMek]

Thanks for the heads up on the duct work, I'll definetly look into that immediately.

[JetMek]

Inspected the duct work last night with a video borescope and found no damage (which is good I guess). Now back to square one...

[Roberson4]

Our 2011 340TG ducted AC hardly blows any air out of the forward AC vents. I have not checked the AC duct work yet. The rear (4 of them) AC vent have good air flow. The rear bathroom get so much air I actually bought a register that has flow restricting (adjustable) flaps in them.

I am also thinking I need to block the heater registers completely somehow. Our 5ver has heater duct in the storage compartments and to the black/gray water tanks. My thinking on ours is: Heat may be raising thru open heat ducts from 'outside' and or cold air may/could be escaping out thru the heat ducts in the floor.

I know this thought has nothing to do with the very low flow coming from the forward AC vents, but could affect cooling.

[JetMek]

I'm at a loss for ideas, I believe the camper needs a larger A/C unit or even a second one but the camper is only equipped with 30amp service. I'm curious to know if any other 31sqb owners has this problem. Of course Keystone says no but I'm not convinced.

[JRTJH]

JetMek,

When we first got our RV, I took all the A/C registers off the ceiling and found that all but one of them were not sealed to the ceiling. In other words, the cold air was flowing through the ductwork, but at the registers, it was leaking into the ceiling joist area rather than being forced into the camper. When I held my hand to a register, it felt cool, there was some air flow, but after I used aluminum duct tape (not fabric duck tape) to seal all the ductwork to prevent air loss, the velocity of cool air doubled and our RV was much MUCH cooler. Also take the A/C ceiling cover off, look carefully at the area around where the forward and rear ducting is connected. I found that we had almost an inch of open space where air was being blown into the ceiling, not into the ductwork. Once those leakage issues were resolved, our A/C was much more able to cool our RV, even in 100+ weather last July when visiting North Carolina. I won't say it was "frigid" inside, but we were comfortable, even with the sun beating through the big back window.

John

[f6bits]

Does your A/C have the “feature” where you slide a lever at the AC main vents and it sends all cold air straight down? It’d be nice to get a feel for how much and how cold the air is coming out of the AC.

[Bob Landry]

It will not keep the 20 degree drop in temperature from outside temp to inside temp as published. It was 90 degrees outside and I couldn't get the inside temp below 80-82 while my neighbor campers were in their cozy 70-72 campers. I need to know if this is a 31sqb issue or a Keystone wide issue..?

Published where? The 20 degree drop that is frequently mentioned is the difference between the discharge air from the AC and the return air being pulled back in it from the inside. It's also known as the split across the coil. It has nothing to do with outside temperature. There is no air conditioner manufacturer that specifies that their unit will maintain an outside/inside temperature differential. if you are told that, it would be coming from a dealer/salesman, and he is mis-informed.

That said, even a 15K BTU unit is undersized for the size trailer you are trying to keep cool. You may be able to help it some by pulling the grill and air registers and making sure that all of the discharged air is being ducted into the trailer and not leaking into the ceiling areas.

[springfield5]

My wife and I bought our Cougar this spring but have not had a chance to use the A/C. Since I only have it hooked up to a 15a circuit I can't run the A/C but can tell you that all of my celing vents have plenty of air flow when the fan is on...much more than I expected suprisingly. Our next trip isn't for a few weeks so I will be able to update on the performance then. Also, we will be spending a little time in the Florida Keys this summer so that should be the ultimate test. Please keep us informed if you find anything wrong but I suspect it just may not be up to the task given that the unit has been replaced with the same results.

A good idea, as previously stated would be to open the "main room vents" located on the bottom side of the A/C unit and check the outlet air with a thermometer and then compare it to the ceiling vents. This may help determine if the A/C unit is sub-par or if it is a ducting problem.

I hope you find the cure and good luck.

[JetMek]

thanks for all the concerns and questions, the dealer is currently getting ahold of Keystone to have them take it and check it themselves since I live close to where they're manufactured. I'll keep you updated.

[bgilly]

I'm not a very active member here (too busy with my real job) but I believe I can lend some assistance in diagnosing A/C problems. I do have HVAC background if that helps add "clout" :rolleyes:

Some have already mentioned the 20 degree difference. Here is the scoop on the 20 degree rule. A healthy, properly installed unit will have a 20 degrees split between return temp. and supply temp. This should be measured with the same thermometer. Basically take the reading at the return grill (typically right under the unit) and then take a reading at the closest discharge (preferably not right at the A/C with the quick cool damper). You should measure a 15 - 20 degree split between the two.
Anything less than 15 degree could be a leaking gasket between the discharge baffle (plenum) and the return. This is an easy fix by sealing baffle separating the two sides. You should remove the ceiling trim to do this properly.

If the split is greater than 20 degrees, the first and easiest causes are air leaks. Other causes could be an undersized unit or poor system health such as a dirty coil (inside coil or outside coil), low refrigerant, faulty compressor and other mechanics of the A/C system.
Air leaks can be mostly on the supply air side and as some have already pointed out the ducted system be a weakness. But don't just check at the grill but also at the unit itself. That is where the air pressure is highest. The air leaves the unit into the discharge plenum. The plenum splits into two ducts. On the port side one duct goes to the front of the camper on the starboard the duct goes to the rear (or could be vice-versa). I have found poorly sealed ducts to the A/C plenum causing significant amount of air to dump into the ceiling and never reach the living space. You again would need to remove the ceiling trim to inspect. It there are gaps in either plenum or to the duct you can seal them with foil tape that can be purchased from Home Depot. Contrary to its name, don't use "duct tape", it doesn't work well.

If the duct and plenum look OK, then close off half the grills on each duct run leaving the grills closest to the A/C unit open. Close doors and drapes. See if the temp begins to drop to a comfortable level. If it does, your A/C is just too small for the amount of heat in the camper. Most campers can do fine with a 13,500 BTU A/C unit but if you have a lot of people, cook inside a lot, leave a lot of lights on, have all the shades or curtains open and parked in a very sunny site, you have created a substantial amount of heat load for the 13,500 BTU of air conditioning. A 15K BTU would improve the heat removal ability but my thinking is to look for the heat sources first before upgrading to a higher BTU A/C.
Also, don't expect and A/C unit to cool down a 100 degree plus camper in a mere 30 minutes. Part of the job of the A/C is not only to remove the heat but also the humidity in the air (this is why you see water dripping from air conditioners - they are conditioning the air).

Well, that is my input on the A,B,C's of the air conditioner.
I have a good technical write-up I put together a few years ago on RV air conditioner units. I would be glad to share it here if there is interest in it.

Good luck and remember to use caution.

Bobby

[CincyGus]

As mentioned, I think your asking a lot of a single AC for that size camper. Besides the advice you have already been given on making sure the ducts are taped well and checking temps, I'd ask if your windows are tinted and/or do you leave your shades closed during the day? Also, are you using any insulation in roof vents such as the inflatable pillows you stuff in the 14"x14" crank vents? All of these things can help reduce the amount of sun that is beating in and improve your AC's ability to help cool your unit.

I only have a 23' Passport UL with a 13.5 and it frankly freezes us out and I like it cold. I camped week before last and with the highs in the lower to mid 90's all week, my camper never got above 72 degrees during the day with the thermostat set at 69. I did do the above (shades closed by noon and inflatable pillows in the vents. My girls slept with sweatshirts on and sheets and blankets on their beds.

[JetMek]

Thanks Bobby for the advise, I did inspect all the duct work as you mentioned with a video borescope and found it all to be good. The plenum was not sealed very well so I foil taped that up as well. I'll try taking temp splits the next time we got hot around here in Michigan (up and down weather). I still believe the unit is too small for my camper but the dealer and manufacturer disagree with that and I'm currently working with Keystone on taking it back to the factory to get tested out there since the dealer gave up.

[JetMek]

BTW the dealer agrees with me that the camper isn't cooling like it should but states the a/c unit is good. hmmmm

[Bob Landry]

The 20 degree split is only applicable if the unit is large enough to cool the space. If it's undersized, you will never see the split, even if it is correctly charged. An amp measurment on the compressor will tell if it's charged correctly. If it is, and you don't get the split, then it's undersized. The good thing about the amp check is that it's valid even if you are leaking air due to a duct problem.

[Jay Pat]

On my trailer, I found inside the unit where the partition between the "cold air" and the "return air" was short and was allowing air escape over. I found this when checking the filter. Was able to fix with cardboard filler on the bottom of the partition.

Is your outside door used often? Kids coming and going?

I made outside covers for the windows and frames with Reflectix and is held in place with Industrial Velcro. The frames bring in heat, too! This is used when parked.
Hope this is helpful!!
Pat

[bgilly]

The 20 degree split is only applicable if the unit is large enough to cool the space. If it's undersized, you will never see the split, even if it is correctly charged. An amp measurment on the compressor will tell if it's charged correctly. If it is, and you don't get the split, then it's undersized. The good thing about the amp check is that it's valid even if you are leaking air due to a duct problem.

Bob, this is not entirely true. You can get a 20 degree difference if the unit is slightly undersized, it just takes longer.
Amp values are not accurate either since voltage variations directly influence amp draw; the lower the voltage from name plate the higher the amps, the higher the voltage - lower amps. Not every power outlet is going to be right at 120 volts ac.
A unit very low on refrigerant will have to work harder and also cause the compressor motor to run hotter therefore pull more amps, so amp information can be helpful for indepth troubleshooting.
Running the camper on longer power cords, poor power outlet connection and other factors result in amp levels.

JetMek, I recall you stating you inspected the duct work but I understood you checked it at the discharge (grill) but I understand that you inspected the duct from end to end. Every camper I've owned with ducted A/C had poor sealing at the A/C unit discharge (plenum). I also had a similar issue that Pat mentions between the return and supply. I fixed mine with weatherstripping.

Bobby

[Bob Landry]

Amp values are not accurate either since voltage variations directly influence amp draw; the lower the voltage from name plate the higher the amps, the higher the voltage - lower amps. Not every power outlet is going to be right at 120 volts ac.
A unit very low on refrigerant will have to work harder and also cause the compressor motor to run hotter therefore pull more amps, so amp information can be helpful for indepth troubleshooting.
Bobby

The amp draw check is relative to outside ambient temperature, not line voltage. The compressor amp draw shown on the name plate is at 95 degrees. The change in amp draw is 1 amp for every 10 degrees shift in temperature, plus or minus. A compressor that is stated to draw 12A @ 95 degrees will draw 12.5A @ 100 degrees, 13A @ 105 degrees, etc. This is for a correctly charged unit. I don't know if this would also apply to residential or comercial units, I havn't asked, but this comes from Dometic, not me, and it is how they will tell you to check one of their units for proper charge without having to tap into the system with a piercing valve. If the unit is low on charge, it will draw less than the stated amerage, so an undercharged unit actually works less because of the reduced charge. I was skeptical when I was first told about this, but I've checked it against a couple of units and it does work. I serviced one last Saturday that wasn't cooling and it was drawing around 6.5A. I sweated in a shraeder valve, evaciated it and weighed in a charge and checked it again, and the amp draw was within .1A of where it was supposed to be.

[Hansel]

On my trailer, I found inside the unit where the partition between the "cold air" and the "return air" was short and was allowing air escape over. I found this when checking the filter. Was able to fix with cardboard filler on the bottom of the partition.

Is your outside door used often? Kids coming and going?

I made outside covers for the windows and frames with Reflectix and is held in place with Industrial Velcro. The frames bring in heat, too! This is used when parked.
Hope this is helpful!!
Pat

This was my fix also, I thought I had a a/c unit gone bad but the camper place said the return for the a/c unit need some tape work and believe it or not it worked. A/C is kicking butt again

[BldrRob]

We have the same 31sqb with 30amp service and only 1 ac unit. We live in Austin and get out at least once a month. We bought it in March 2011. I would say that, yes, ours has been able to keep up with hot temps but I'm not 100% happy. I think it should have 2 units. We have tripped the breaker several times when nothing else is being used. IMO this rig should have 50 amp service and be set up with dual a/c.
Hope it works out for you. Keep us in the loop.

[happytrails]

I have owned a 31SQB since August of 2011. I wouldn't say that the AC is not working properly, but I would say that it may be undersized for this length of trailer. On really hot days 90+, it does just an okay job of cooling. I think it usually comes in around 78 or 79. It definitely doesn't hit any type of 20 degree difference except at night maybe. Mostly I have been attributing this to my kids going in and out and in and out and you get the point.

However, I have seen a lot of great ideas mentioned about blocking off heat ducts, chekcing the AC ducts, and a few others so I will definitely be looking at some improvement techniques. I had a similar size AC unit in my dinky little popup and we froze to death in there. I have put a vent pillow in my back vent in the bunk area to help out, but I don't know how much it really does. I would have preferred a larger unit or dual units as others have mentioned, but I can't see spending the money on that now. We bought the RV for the comfort for when we are actually in it, but when we go camping, pardon me, RVing, we are outside 90-95% of the time we are not sleeping and at night it cools off very well.

I hope that the OP gets the issue(s) resolved. I do like my Keystone RV. For the price it's been wonderful so far. We have been "camping" about 15 times since owning it and have 5 or so more trips planned this year.

Edit***
Well I took apart some of the AC duct work and the main cover to the unit inside. I found that the duct work really appears to be cardboard duct which is interesting I guess. All the connections and the volume of air seems to be very good. When I opened up the cover to the main unit I could see that the tape job there was just horrible. I will be removing the factory tape and going to Lowes for more tape if I can't find mine in the basement. Just a poor job on that, how disappointing. Anyway, I have no real way to take the entire ceiling down so I will just have to be okay with hoping that the rest of the cardboard duct work is taped or sealed well. I can't imagine what a chore it would be to take all that stuff off.

Edit #2***
Here is what I found. The first three show bad tape job in main unit. The last picture is just of up inside a ceiling vent showing the cardboard-like duct work. I'm not exactly sure what it's made of but felt like the inside of a shoe box.

http://www.keystonerv.org/forums/picture.php?albumid=226&pictureid=1018
http://www.keystonerv.org/forums/picture.php?albumid=226&pictureid=1019
http://www.keystonerv.org/forums/picture.php?albumid=226&pictureid=1020
http://www.keystonerv.org/forums/picture.php?albumid=226&pictureid=1021

[Hansel]

I just don't understand why the A/C is so poorly installed:( I just returned from a week of camping which went way too quick:eek: and was cleaning up the camper when I decided too remove the grill covering the A/C unit, and WOW what a poor job of appling A/C tape, I would think that they would have some type of duct working like your home A/C not this exposed spaces and frame work. I think Keystone needs to look at how A/C unit's are plumbed into the roof and fit a poor installation practice.

[springfield5]

Maybe we got one of the good ones? We spent half of last week camping in 97 to 101 degrees. The inside felt more than comfortable and chilly at night. I just ordered an indoor / outdoor thermometer so I will be able to tell you the actual temps soon...not just my feelings. I did however re-tape the inlet duct before we left thanks to all of the previous input. I also removed the outside cover (on the roof) and taped the return duct. There are many places that air can escape creating inefficiencies. Most can be easily remedied with some foil tape...however I would agree that we should not have too after paying so much money for a quality trailer! Good luck with your A/C and I hope they get everything handled for you.