Free 7 Day Trial RV GPS App RV Trip Planner Campground Reviews RV Maintenance Free 7 Day Trial ×
 

Go Back   Montana Owners Club - Keystone Montana 5th Wheel Forum > GENERAL DISCUSSIONS > General Discussions about our Montanas
Click Here to Login

Reply
 
Thread Tools Search this Thread Display Modes
 
Old 06-18-2021, 04:22 PM   #1
Tarheel5
New Member
 
Join Date: May 2021
Location: Grand Rapids
Posts: 3
M.O.C. #28762
Air conditioning

Sorry for another newbie question main a/c does not seem to blow cold air. Current outside temp is at 82 bedroom unit is turned off currently plugged in on seasonal lot thermostat set at 67 and it’s hot. Any suggestions
 
Tarheel5 is offline   Reply With Quote
Old 06-18-2021, 04:41 PM   #2
DutchmenSport
Montana Master
 
DutchmenSport's Avatar
 
Join Date: Oct 2018
Location: Anderson
Posts: 930
M.O.C. #22835
Get a thermometer and put it right at the outlet vent and get the actual temperature of the air blowing at that point.

Once an RV get's hot, they are hard to cool down. The space is just too much, there are too many drafts, the insulation in the ceiling and walls is nothing compared to your home. Add the space of the height of your ceiling, the space of the slide outs and that's a lot of space for a single AC to cool.

In order to cool and keep the camper cool, the AC really needs to be started in the morning, and both AC's need to be running. One by itself just can't do it, that's why the manufactures installed 2 of them.

In a pinch, you can retract all your slides, reducing the space to cool. Then once the main body of the camper cooled down, open one slide and let the system equalize again. Then open the next slide. This is how we do it after traveling all day and first landing at the next campsite and the inside of the camper is 95 or 100 degrees.

Your best bet is to use a thermal thermometer and shoot the beam directly into the outlet vent and see what's really coming out there, what the temperature actually is.

In my Montana High Country (41 feet long with 4 slides), the temperature blowing out of the closest vent to the AC is 45 degrees. In the middle of the camper, the kitchen countertop reads 78, the walls 80. Of course outside temperature and a cloudless day and being under trees or in direct sunlight makes a big difference in those temperatures too.

Again, check the actual temperature at the vent. If it's blowing warm, then something else is going on, most likely the settings on your thermostat.
__________________
DutchmenSport
2019 Montana High Country 375FL
2014 Chevy Silverado Duramax, 6.6L Dually
DutchmenSport is offline   Reply With Quote
Old 06-18-2021, 07:07 PM   #3
MARK A
Montana Master
 
Join Date: Jan 2016
Location: STAYTON
Posts: 1,028
M.O.C. #18157
Open the vents and run the fans on low for a couple hours. It allows the hot air to escape and be replaced by colder air. But the early start is the long term solution.



Mark
__________________

2016 3610/2012 F-350 Powerstroke
MARK A is offline   Reply With Quote
Old 06-19-2021, 08:10 AM   #4
1retired06
Montana Master
 
Join Date: Feb 2012
Location: Lake Gaston
Posts: 8,374
M.O.C. #12156
You said you were a newbie, and not getting cold air. I would start with the compressor. First thing I would do is turn on the AC, listen to see if the compressor kicks in. If you do not hear it kick in, let the AC run for a while, go outside and see if you are getting any condensation drip down the side of the rig. You should see water drip. Assuming no drip hole blockage, the compressor is not operating. No compressor, no cold air. If it is operating, I would next check the vents to see if they are blocked. If they are not blocked, I would continue with the advice provided above.
__________________
Mike and Lorraine
2002 3655 FL, 2005 3650RK
2010 3665RE, 2015 3910FB
F350 crew cab dually 6.7
1retired06 is offline   Reply With Quote
Old 06-19-2021, 06:36 PM   #5
Chief Brown
Established Member
 
Chief Brown's Avatar
 
Join Date: Jan 2021
Location: Cumming
Posts: 29
M.O.C. #27901
I have another ac question. We have a 2021 H/C 331RL. The thermostats have both a “High Cool” and I “Low Cool” setting. What’s the difference?
Chief Brown is offline   Reply With Quote
Old 06-19-2021, 06:54 PM   #6
DutchmenSport
Montana Master
 
DutchmenSport's Avatar
 
Join Date: Oct 2018
Location: Anderson
Posts: 930
M.O.C. #22835
Quote:
Originally Posted by Chief Brown View Post
I have another ac question. We have a 2021 H/C 331RL. The thermostats have both a “High Cool” and I “Low Cool” setting. What’s the difference?
The speed in which the fan blows.
__________________
DutchmenSport
2019 Montana High Country 375FL
2014 Chevy Silverado Duramax, 6.6L Dually
DutchmenSport is offline   Reply With Quote
Old 06-19-2021, 06:55 PM   #7
Chief Brown
Established Member
 
Chief Brown's Avatar
 
Join Date: Jan 2021
Location: Cumming
Posts: 29
M.O.C. #27901
Duh!! Thanks
Chief Brown is offline   Reply With Quote
Old 06-27-2021, 02:47 PM   #8
bcrvman
Montana Fan
 
Join Date: Jun 2020
Location: Qualicum Beach
Posts: 287
M.O.C. #26399
Quote:
Originally Posted by Tarheel5 View Post
Sorry for another newbie question main a/c does not seem to blow cold air. Current outside temp is at 82 bedroom unit is turned off currently plugged in on seasonal lot thermostat set at 67 and it’s hot. Any suggestions
67? Normal recommended setting is 75. Is the compressor running, do you see water flowing off the roof? Is it a real ducted system or an RV spot cooler? The later do not work well under the best conditions. Good luck!
__________________
2018 Keystone Montana 3811MS
2017 Ford F450 diesel dually
600AH Battle Born Lithium Batteries, 1,080 watts solar
3,000 watt hybrid inverter with 120A charger
bcrvman is offline   Reply With Quote
Old 06-27-2021, 03:11 PM   #9
DavidG425
Established Member
 
Join Date: Dec 2020
Location: Hemet
Posts: 11
M.O.C. #27789
We had similar problems. RV tech explained that when the sun hits the roof, it heats up the styrofoam insulation and the "ducts" that are cut into them. Once the ducts cool down, you'll get cooler air out of the vents.

Check out http://www.shaderv.com
We have one and it helps A LOT!!!
DavidG425 is offline   Reply With Quote
Old 06-27-2021, 05:10 PM   #10
Bob and Jeannette
Montana Fan
 
Bob and Jeannette's Avatar
 
Join Date: Sep 2018
Location: Orlando
Posts: 259
M.O.C. #22589
Air conditioners work well if they are not broken. 82 is not hot at all, mine work in Florida humidity and 96 degrees. IMHO something is not correct on your system.
__________________
2020 Montana 3813ms legacy w/Paint
2017 Ram 3500 4X4 DRW Aisin Curt Q-25
Bob and Jeannette is offline   Reply With Quote
Old 06-27-2021, 05:15 PM   #11
kdeiss
Montana Master
 
Join Date: Feb 2003
Location: Englewood
Posts: 3,095
M.O.C. #164
Quote:
Originally Posted by Tarheel5 View Post
Sorry for another newbie question main a/c does not seem to blow cold air. Current outside temp is at 82 bedroom unit is turned off currently plugged in on seasonal lot thermostat set at 67 and it’s hot. Any suggestions
Your temp coming out of the AC should be 18 to 20 degrees higher then the temp going in if not you have a problem !!
kdeiss is offline   Reply With Quote
Old 06-28-2021, 06:15 AM   #12
Dam Miller
Established Member
 
Join Date: Jul 2018
Location: Magnolia
Posts: 15
M.O.C. #22119
Remove the cover on the air return and look at the duct (cell phone camera can help). Some have had problems with the duck collapsing. This was the problem I had right from the sales lot. I cut pvc pipe into sections and then pushed them into the ducts. No more collapsing.
__________________
Dam Miller is offline   Reply With Quote
Old 06-28-2021, 02:11 PM   #13
Bob and Jeannette
Montana Fan
 
Bob and Jeannette's Avatar
 
Join Date: Sep 2018
Location: Orlando
Posts: 259
M.O.C. #22589
Quote:
Originally Posted by Dam Miller View Post
Remove the cover on the air return and look at the duct (cell phone camera can help). Some have had problems with the duck collapsing. This was the problem I had right from the sales lot. I cut pvc pipe into sections and then pushed them into the ducts. No more collapsing.
I noticed this also when troubleshooting mine. It appears that they applied insulation to the inside instead of the outside of the ducts. So where the are is sucking in the styrofoam insulation tightens up.

Please let me know if anyone has a fix before I do mine.
__________________
2020 Montana 3813ms legacy w/Paint
2017 Ram 3500 4X4 DRW Aisin Curt Q-25
Bob and Jeannette is offline   Reply With Quote
Old 06-28-2021, 08:39 PM   #14
MoblieHilton
New Member
 
Join Date: Apr 2019
Location: Jacksonville
Posts: 2
M.O.C. #23902
I have been battling the AC issue from Day one.. there are several things you need to look at to improve your systems.. First is to remove all your ceiling ac vents and check the foil tape sealing the ducts.. I found all of mine had one layer tape and all had tears and holes allowing hot attic air infiltration.. I added 2 layers of foul tape to seal all ceiling duct openings.. second while the vents was out I trim the vent insert that was protruding in the duct about a inch to be level with the opening, then took out every other slat out of the rotating insert to increase air flow.. I also had in the beginning if found the return air ducts collapsed, so the dealer install the PVC to keep the return air ducts open.. This past weekend I added other mods to help.. I took out the PVC yhe dealer added and a
Replaced with a 1.5 flexible hose in each return duct..approx 3 feet long each (I used pool vacume hose).. to keep the ducts open the full length of the returns.. while I had the AC's off I also added a piece of metal in supply box bent in the middle then bent to make like a scoop to send air directly to each supply ducts. I the foil taped in supply duct with the peak in the middle under the squirrel cage to balance the air flow to each supply duct. While you have the units open clean and service the cos and check you frost sensors to make sure they are in place on the coil.. one of mine was off.. Lastly I changed out the Dometic thermostats out to Microairs thermostats (pricey but well worth the investment) The air flow is much much better.. It was 90 degrees in unit when I got done with mods.. took about 1.5 to 2 hrs to get coach to 75 degrees and was able to maintain that throughout the afternoon...this weekend will be the true test... hope this helps!!
Attached Thumbnails
Click image for larger version

Name:	20210627_130649.jpg
Views:	8
Size:	155.4 KB
ID:	9508   Click image for larger version

Name:	20210627_130458.jpg
Views:	6
Size:	166.7 KB
ID:	9509   Click image for larger version

Name:	20210627_130644.jpg
Views:	8
Size:	89.0 KB
ID:	9510   Click image for larger version

Name:	20210627_130441.jpg
Views:	5
Size:	204.5 KB
ID:	9511  
MoblieHilton is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by Montana RV, Keystone RV Company or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 06:38 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2021, vBulletin Solutions, Inc.