A/C

[HOOK]

It would appear to me that high end 5er with two A/Cs would be expected to cool comfortably on a hot day. When only 2 models from among 10 have this flaw and the others cool very well, it does not suffice to say that the intake air is 21 degrees warmer than the output air . Especially when the 3750frontliving living room is uncomfortably warm. Someone needs to find a solution.

[K0LCB]

So far my front lounge stays cool. I removed the two diffusers for more air flow

[DQDick]

Your right Larry. We've already heard too much about this problem.

[slfaircloth]

We have tried:
Cutting down the sleeve of the diffusers
Running a fan from the kitchen area to the living room
Running the ceiling fan
Forcing the fan on both units to run on high
Removing the diffusers
Running the Fantastic Fan in the living area on low, medium and high
Calling Keystone Owner Relations - they told us as long as the temperature was 21 degrees cooler on output that intake, the unit is performing to specifications and they have no further suggestions.
This is not cool figuratively and literally. After paying all that money for a world class, best selling RV, you would think we should be comfortable. Not so. If anyone is considering a 3750 or 3850, take my advice and don't do it until Keystone steps up and resolves this design flaw.

[jimcol]

quote:Originally posted by slfaircloth


Calling Keystone Owner Relations - they told us as long as the temperature was 21 degrees cooler on output that intake, the unit is performing to specifications and they have no further suggestions.

All that the 21 degree differential says is the A/C unit is working properly. If it still doesn't cool the 5'er they have a duct design or distribution problem. I agree with you and others. As many times as we are hearing this They need to step up. Jim

[Irlpguy]

Larry it is not just two models that have an issue with the AC, ours was originally the intake ducts from each side of the living area being collapsed, that was fixed by the dealer supposedly but made little difference to the cooling ability of the unit. On a 90 degree day with slide toppers and the blinds down I should be able to keep the unit at least 10 degrees cooler than the outside air, that don't happen.

I have a window AC in my SB and it cools a large living room and family room to a comfortable temp at 90 degrees outside and that is with a tar and gravel roof with poor insulation.
I think we all got the "Arctic" package but not as far as the AC is concerned.

[HOOK]

I guess the ultimate question is, when a person buys a new expensive luxury 5er, should they not expect to be comfortable on a hot day? I don't think it is unreasonable.

[Ozz]

I agree HOOK, you hit the nail on the head buddy.
In my 2007 3400RL, the darn things are so noisy I hate to be somewhere I have to run both of them. I hear some newer models have a quieter noise level inside, maybe these are units that cool better.
There is just not enough insulation in the overhead, I bet slide toppers do help, but insulation is a factor there also.

[1retired06]

Yesterday I lost the rear 15K AC on my unit, and have a matching unit on the front. When the new AC was installed, the technician pointed out the sloppyness with which Keystone installed the unit, only three bolts held the unit in place allowing one corner of the gasket to lose air and potential for water to leak in. The support bracket was not installed. The duct divider was not installed. The ducting sealing tape was not installed, which allowed signifcant lose of cool air. Replacement unit was the same exact unit, and I could immediately feel major difference in the coldness of the air when holding my hand up to the vent. Yes, it is still just as noisy.

[Ozz]

It is amazing how a good install mirrors the directions that comes with the unit. I read and re-read the directions when I installed mine, many 'wing it'

[1retired06]

Disappointing to find out Keystone wings it on the production line, at least on my unit.

[HOOK]

quote:Originally posted by Ozz

I agree HOOK, you hit the nail on the head buddy.
In my 2007 3400RL, the darn things are so noisy I hate to be somewhere I have to run both of them. I hear some newer models have a quieter noise level inside, maybe these are units that cool better.
There is just not enough insulation in the overhead, I bet slide toppers do help, but insulation is a factor there also.

Hey Ozz! In all the floorplans except the 3750 and 3850, both front living room models, the "whisper quiet" AC is mounted over the living room and the 2nd AC is at the opposite end of the duct in the bedroom. All of those cool well. The 3750 and 3850 have their ACs mounted similarly with the "wc" mounted above the bedroom, which on these models are at the rear of the coach. The second AC is mounted above the kitchen, maybe ten feet forward of the rear AC leaving about 1/3 of the duct forward of the front AC. The bedroom is very comfortable but the living room is hot. Plenty of airflow in bedroom but just a trickle in the living room, cold enough air but no volume. Obviously the solution is to turn the system around , ducts included, put the 15000 "wc" over the living room and the 13500 second AC in the bedroom , both units at the ends of the duct and the volume will be as good as it is in the other models. You opinion please?

[Ozz]

I read it 3 times and am cornfused, I would have to sit down with you over a set of plans to give a good answer. It sounds like you may have it figured out but I would have to see the ducting in the overhead.
If the volume is too low, there may be too many vents, or openings, restricted ducting, too many 90 degree turns, or a low powered fan, or fan blade. A straight run with a properly designed fan and fan motor, proper amount of outlets and the airflow would be good.
My thoughts are that Montana's designers used an 'off the shelf' unit, not designed for the ducting system and tried to make it work for their duct system. Backward engineering, so to speak.

[RRman]

Well, a new 15K Dometic Brisk Air 2 (Smaller, lighter, quieter) replaced my old Dometic Brisk Air single / main unit and a Coleman Mach 2 13K was added to the Bedroom to deal with parking lot heat in Houston TX while parked North to South (side with most windows faces West) maintains 76 degrees as desired, except when 100 or above and then 78-80 degrees occurs for a short while. However the West facing windows either have awning coverage or "Reflectix" insulation in them and I do have Slide Toppers.

[slfaircloth]

I'll have to say all my complaining did not fall on deaf ears. Camping World came through for us on a solution. They installed a low profile air conditioning unit in place of the Fantastic fan in the front room for a very good price. While I am disappointed Keystone did not take ownership for their design flaw, I am most appreciative to Camping World for doing their part.

[bncinwv]

Sandi,
I take it that means that you have three air conditioners? I also assume the third on has the controls on-board and is not tied to the thermostat? Is the third one tied into the ducting or simply stand alone? My curiosity is aroused.
Bingo

[Ozz]

Thanks Bingo, I wondered as well.

[slfaircloth]

Yes, we now have three air conditioners. The latest addition is a stand alone, not tied to the duct work or the thermostat. We are picking up our coach tomorrow and will be camping in SC this weekend. I'll post here to let you know how it works out, although this weekend may not be the best test since the weather has turned off cool.

[Ozz]

Sandi and Dave, you guys will be the only ones cool in the RV parks you go to. and I'm jealous, one addition I don't have :0

[Hooker]

quote:Originally posted by HOOK

I guess the ultimate question is, when a person buys a new expensive luxury 5er, should they not expect to be comfortable on a hot day? I don't think it is unreasonable.

I think you will find though the Montana is a fine 5th wheel, it is not in the "expensive" class or the "luxury" class of 5th wheels.