Cooling Concerns in 3750FL

[slfaircloth]

The living area gets hot, hot, hot! Seriously in need of more air flow!

[hookman]

If you go to Ozz's A/C mod you could do what he did.
http://www.montanaowners.com/forums/...Terms=AC,vents

[DQDick]

Opening the ducts up, by trimming the vents like Ozz did would definately increase air flow, just only do it on the ones you want more flow from. Also, if you have a front AC, running your fan all the time will also help circulate air from the area's that are cool back to the living room while removing the hottest air for more cooling. For further help we need to know what outside temps you are dealing with and do you have one or two AC units. If you have two are they on the same thermostat or is one operated manually? How often do you clean your filters? Do you have slide toppers?

[bncinwv]

Depends on what year you have. Our 2011 3750 does not have ceiling vents but rather the living room air comes from the end of the vent line which terminates at the kitchen above the steps. First rule if yours is like ours, do not run fantastic fan in living room, it sucks the cool air out before it has time to sink. Second rule, the kitchen fan is your friend, make sure the direction of the blades directs the air down. And final rule, leave the blinds in day shade position to keep the sunlight out. We have been in the 90's here at the beach and we are all cool. Both ac's running with fans set on high and thermostat set at 76.
Bingo

[slfaircloth]

We have a 2013 3750FL just purchased in April. We have two units, no slide toppers and the outside temperature is 85 degrees plus. Service technicians have advised us not to force the fan to stay on high due to the possibility of freezing up the units. Both units are operated by the thermostat (zone 1 and 2). Trimming the register sleeves and even removing them completely did not increase the air flow. We don't have the ability to do what Ozz did - we are not HVAC technicians. We should not have to come out of pocket for resolution as this coach is still under warranty and the expectation of comfort during less than extreme weather conditions should be a given. Wouldn't you agree?

[Irlpguy]

I am with slfaircloth, the units are either inadequate or there is something amiss and it should "not" be the responsibility of the new owner to modify a brand new unit.

Also, not all vents have the same problem that Ozz had, ours are shallow and do not extend into the air vent as his did. Again this should be addressed through the dealer.

I am definitely not impressed with the AC in my 2012 - 3402RL, it is not adequate to do the job.

[jimcol]

quote:Originally posted by slfaircloth

Service technicians have advised us not to force the fan to stay on high due to the possibility of freezing up the units.

I'm not a HVAC tech either but I would have to challenge the service tech on this. Continuous fan will help prevent freeze ups. Continuous compressor w/o adequate fan can cause freeze ups. Jim

[Rainer]

We had a 2nd AC installed in the bedroom at the time of purchase. Although it's just the 13K BTU it cools the bedroom much cooler than the 15K BTU unit in the living area. Our solution was to purchase a powerful floor fan and set it in the doorway of the bedroom directed to the living area while all AC's are at full maximum. This has worked very well for us.

[Ozz]

What jimcol said. The tech had it backwards.
I also do what Rainer does.
This is a good time to recommend that anyone thinking of a unit for the front go with a 15K. I did and recommend it.

[1retired06]

Check my comments on the AC topic just before this one which outlines the sloppy Keystone installation of my rear AC.

[bncinwv]

The only thing that has not been suggested is to have the technicians do a complete inspection of the ducting system. This can be done with a remote camera (like those used for sewer inspections). I would venture to say that you have a blockage somewhere in the duct installation. The other thing that I cannot remember is whether you have one of the square ceiling vents installed in the living room. The sun coming through those clear vent covers may need to be blocked. I strongly believe the problem is with the ductwork, though. We have had both 15,000 BTU's as well as 15,000 and a 13,500 and have been able to keep both rigs cool.
Bingo

[Montana3800RE]

Possibility the return air on the quiet cool system is collapsed like mine and others on here not letting enough air to return to the unit keeping good air flow through the unit to prevent it from freezing up. If you remove a return air grill and get a mirror and look inside the duct you never know what you will find besides a lot of saw dust and who know what else during the construction process, also probably saw dust inside of the a/c unit itself restricting air flow..

[Hooker]

quote:Originally posted by Rainer

We had a 2nd AC installed in the bedroom at the time of purchase. Although it's just the 13K BTU it cools the bedroom much cooler than the 15K BTU unit in the living area. Our solution was to purchase a powerful floor fan and set it in the doorway of the bedroom directed to the living area while all AC's are at full maximum. This has worked very well for us.

Same here for our 3400.

[HOOK]

Ours is a 3455sa with 2 ACs . It does a great job, even at Myrtle Beach in HOTTTT weather.

[Big Dave]

Well I was having problems with my 3750FL cooling too! I trimmed the vents as OZ suggested and found that the unit in the kitchen had a problem also. The divider in it to keep the cold air from going to to the air return was not installed properly, by fixing these two things it made a huge difference in the cooling, it still is not perfect but close!