Very unhappy with new AC system!

[RKassl]

I really didn't think you could use both AC and what ever on 30 amps, I could be wrong but that doesn't sound right.

[bigskyjimmy]

You are right BOB,when on 30 amp you just have to make do with one a/c and grin and bear it

[Golfmedik]

I have the unit at home now to start readying for our trip this weekend, but it won't stop storming! I talked at length with the service manager and he will be talking to Keystone and the Montana service reps to see what can be done. As I said earlier, he had a problem with a Sandpiper last week and called them to which he was told to call Dometic! He told the guys at FR that the unit was cooling as it is designed, but it is in YOUR camper that you built. They have forwarded the complaints from the owner and dealer up the "chain" so to speak. I will be calling Keystone myself as soon as I get the opportunity. Who knows how this will play out, but just wanted to update you guys.

[worleyjrtx5]

On my 2011 Mountaineer, with 2 airs, in Texas, you must have 50 Amps and even then, unless you are under trees as your picture shows, you cannot keep it below 85 degrees when it gets above 100 degrees when the rig is in direct sunlight. 30 Amp just won't let you run both AC and even with 50 Amp running both units wide open when it is over 100 degrees with the rig in direct sun light, it gets hot inside. We do not have slide covers, but do have everything else as others have stated.

[richfaa]

I am also not the only one who has problems with the A/C's keeping the RV cool in hot weather.Who would have thought. The dark colors of our Big Sky do not help.

[rickbecker]

I was very frustrated with the poor cooling in our 2013 3150RL, so started reading posts on this forum. Several folks contributed, but "thanks" go out to mainly Oz who, if I recall correctly, is an AC guy.

Anyway, I estimate that I doubled the air flow out of the system by doing 3 things that I gleaned from postings. 1 - pull down each of the exhaust vents and remove excess material from the vent that sticks up into distribution channel. I took off 1/2 to 3/4 inch off of each with a pair of sheet metal cutters. Easy to do. 2 - on the rear unit I found that the return air ducts were collapsed down to less than 1 inch. I took some 2 inch pvc pipe cut to 8 inch lengths and fitted 2 on each side up into the duct lengthwise. These hold the duct open without restricting air flow to much. 3 - on the front AC unit there is a piece of sheet metal between the intake and exhaust side of the unit that is adjustable for roof thickness on install. I found that the piece had slipped down about an inch allowing air flow directly between intake and exhaust, thus wasting flow and cooling, Solved with a couple of sheet metal screws and sealing tape around the edges.

After doing the above I find that I can pretty much keep the trailer cool on all but the hottest days by running only the rear unit, so 30 amp service works adequately.

Again, thanks to all who contribute to this forum!!

[bigskyjimmy]

I am in 100 degree weather right now with both A/C's on and We are pretty comfy right now and yep I did the "OZ fix" awhile ago and it does seem to help for sure,also on the ceiling vents I cut a few Louvers out so the air blows Down instead of towards the roof, and I was thinking of installing white grates to install in the ceiling vents instead of those Louvers so all the air goes DOWN I just have to find a way of doing it so it looks nice.....well off to the hardware store I am on a Mission

[Golfmedik]

Its been a trying week here in Myrtle Beach. On Sunday, the temp was 95 and the temp in the camper was 82* on 50A with both units on. I removal oc the vent covers and it made a considerable difference. Also, with both units running, the right side of the camper duct work has much more air flow than the left side. The temp between vents as far as temps is considerable. The ones at the rear unit was 56* air, the next ones a few feet away were 61 and the next were at 64. The front unit was only 64* coming out of the unit this week. Another thing that bothers me is the top of the duct is much warmer than the air that bas been going through it for two days. Removing the vent covers brought us more air volume and lowered the temp by 2*. We are very comfortable at night, but not the day. Still waiting on Montana and Dometic to call dealer back. What really ticks me off is my old Sandpiper is sitting right behind me and has gotten to 77* at its hottest!

[fauch]

We camp regularly on the Florida gulf coast. We have a 2007 3075 RL (three slides). Both AC units are 15.5k conventional type with the rear one ducted.We only use both units with initial cool down. On the ducted unit we have adjusted the main outlet on the unit to force more air into the ducts. When connected at the house (30 amp) for loading, unloading and cleaning, the trailer cools to 65 with one unit running.

Some things that we do to help with cooling are to always keep the basement storage doors latched tight against the gaskets. Inside air is allowed into the basement through the furnace return 'grill slots' in the bedroom step, so the basement is part of the cooled space. We also keep the upholstered cushions from Camping World in the roof vents and have covers on all three roof vents. Our bedroom windows are all blocked with removable foil colored bubble wrap. The shower skylight has foil between the two panes.

[rmthelen]

Our unit has a vent grate in the step area for the furnace which was allowing a lot of warm air to enter into the living area from the cargo area. I sealed the vent off and it seemed to help with cooling the unit. It is worth a try if you have the same furnace vent.

[dieselguy]

rickbecker ... below is an old post of mine from 2011. Read thru it and follow some or all of my suggested mods. You won't believe what a difference your ole 3150 will show. The vent under your fridge and the under stair vents attach to a large open area under your fridge and steps. It is not in any way sealed between your floor beams out to your main storage area or down into the belly. Cold air just pours out to the ground via the clearance holes cut in your belly pan and as you noted, the storage doors don't seal the best either leaking cold air there as well. Ever notice how cool the storage area is should you open a baggage door while the A/C is on?
http://www.montanaowners.com/forums/...ms=design,flaw

[rickbecker]

DG - thanks for the link! Have to drop the belly skin to go after a tank leak anyway, so sealing up and adding insulation where I can will be done. I did the under fridge closure a while back as it just made no sense.

Thank you for your posts!

[Golfmedik]

To help with the heat, I've painted the skylight and the MaxxFan covers white with Krylon paint. Same as all of my other campers. Lets all of the light in but no heat. We always keep all basement doors closed during the day.

[DQDick]

We have insulation pads in the vent openings, shower skylight is smoke on the outside and white on the inside, slide toppers, window awnings, foam board in some windows and 7 solar panels on the roof at PT today were asking me for ideas on how to help their stick house AC's.

[richfaa]

If u want a shock buy an IR thermometer and shoot the temps on your outside gel coat in the sunlight.
Those of us with the pretty Big Sky or full body paint will get a even bigger shock but will help to understand why the A/C dos not keep us as cool as we would like.

We will be heading to Nebraska for a MOC rally then down to Shawnee,Ok for a FCRV rally.It will be very hot and our two perfectly operating A/C's will be running day and night to hopefully keep us comfortable in this pretty dark colored Big Sky. We have never been uncomfortable in very hot and humid temps just wringing out the humidity aids in the comfort level but we have never seen 60's or 70 degrees on a 100 degree high humidity day.Our set point is 77 degrees both A/C's run day and night and at 100 degrees will not get it down to that set point.

[Golfmedik]

Yes sir, I have an IR thermometer and have been taking many readings over the past few weeks and keeping a log. I did discover by accident, that REMOVING the vent covers from the vents, you ADD a tremendous amount of downward air flow that cools the rig MUCH better. The vent covers themselves force the air out along the ceiling, which is warm. Once they are removed, the air comes straight down and at a much greater volume. The temps inside the rig have now been much better since discovering this. Plus, the vents don't look that bad with the covers removed! This one thing truly made a big difference!! I'm a lot happier than I was, but still concerned!

[bigskyjimmy]

Yep already did that Mod to the louvered vents in the ceiling and it Works great ,I have no idea why RV Mfg's angle them towards the hot ceiling,I took my Dremel with the cut off wheel and cut the louvers out and I am going to the hardware store and buy some metal grate mesh and cut it to fit inside the covers and paint the grate white to match the covers

[jcurtis934]

Vents have angled covers to flush cool air across hot surfaces to cut down on amount of heat that can radiate into the room. Same reason hvac designers put vents in the sticks and bricks to flush air on the windows. But, hey, these things are just nice shoe boxes...and that "r21" coated bubble wrap insulation is all marketing hype. Besides, it is just thrown in an area and not sealed in any manner around the edges. You want cool...low seventies on the oregon coast. Okay, that last remark was just to make all you folks sweltering in the heat to hang your heads. Another tip though...look up at each of your 14x14 vents. Notice all the gap between the inside trim and the actual fan housing...seal that with silicon to stop hot attic air from leaking in. Good luck to all in the pursuit of better cooling... John

[rickbecker]

I ordered these to replace existing diffuser- they work great and allow direction and volume flow adjustment. Snap the old ones off then drill small screw holes for mounting these. Look good and as well.

http://www.pplmotorhomes.com/parts/c...FQkwaQodgTQApw

[bigskyjimmy]

Wish I would of read this post before I got Dremel Happy Oh Well it gave me a good project for a rainy day on the Coast and when I turned on the A/C to see how it felt it works great nice cool air going straight down at me AAAHHHHHH

quote:Originally posted by rickbecker

I ordered these to replace existing diffuser- they work great and allow direction and volume flow adjustment. Snap the old ones off then drill small screw holes for mounting these. Look good and as well.

http://www.pplmotorhomes.com/parts/c...FQkwaQodgTQApw