Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 

Go Back   Montana Owners Club - Keystone Montana 5th Wheel Forum > MOC Technical Forums > Additions & Improvements
Click Here to Login

Reply
 
Thread Tools Search this Thread Display Modes
 
Old 08-24-2020, 04:19 PM   #1
glendodom
Montana Fan
 
Join Date: Sep 2018
Location: Terry
Posts: 153
M.O.C. #22698
Adding a 3rd Air Conditioner

We have a 2018 40' Montana, Model 3721RL which came with 2 ACs: 1 living room area 15,000 AC w/HP and a 13,500 AC in the BR.
These units run on a central duct system and are independently controlled by single zone Dometic Duro-Therm single zone thermostats versus controlled via the "In-Command" as later models.

The LR area has always taken an extended time to cool down when arriving at a campsite when the temps are up in the high 90s and likewise struggles during the mid-afternoons when temps are at the highest.



The RV came prewired for a third AC unit which I am considering adding a third unit.

As I understand, when running the 3 AC system there is a control panel that controls the BR and 3rd AC to ensure that all three compressors don’t kick in at the same time but subsequently you can run all three units, correct? I have read comments which indicated ya and nay? Who has 3 units installed that can clarify how the 3 unit system works?


I am looking at adding a low-profile, Penguin II, 13,500 unit, model 641816CXX1J0. (High Capacity Low Profile Rooftop Air Conditioner, Ducted or Non-ducted application - Pre-installed Multi-Zone CCC II control board)
 
glendodom is offline   Reply With Quote
Old 08-24-2020, 06:29 PM   #2
Carl n Susan
Site Team
 
Carl n Susan's Avatar
 
Join Date: Oct 2005
Location: Carmichael - CA
Posts: 7,323
M.O.C. #4831
The Search facility is your friend
https://www.montanaowners.com/forums...ad.php?t=70966
https://www.montanaowners.com/forums....php?p=1109746
https://www.montanaowners.com/forums....php?p=1138854


and that is just a start
__________________
Carl (n Susan)
There is more to life than fuel mileage.
2012 Montana 3700RL Big Sky Package towed by a 2015 Ford F350 6.7L PSD 4WD CC LWB

Carl n Susan is offline   Reply With Quote
Old 08-24-2020, 07:47 PM   #3
DQDick
Site Team
 
DQDick's Avatar
 
Join Date: Jun 2011
Location: Wilsey
Posts: 18,799
M.O.C. #11455
If you use the factory setup the third AC will only run when the bedroom one shuts off.
__________________
Dick, Joyce, Diego, Picatso and Gustav
2017 3720 RL, and 2013 HC 343RL
Pullrite Hitch, IS, Disk Brakes, 3rd AC, Winegard Traveler, Bathroom door mod, Dometic 320, couch for desk swap, replaced chairs, sun screens, added awnings, etc.
DQDick is offline   Reply With Quote
Old 08-24-2020, 08:30 PM   #4
glendodom
Montana Fan
 
Join Date: Sep 2018
Location: Terry
Posts: 153
M.O.C. #22698
Thanks. After reviewing all of that I may have to have a double shot and rethink the 3rd unit. Not sure the 3rd operating in alternate mode is worth the $$. No doubt having 2 running in the LR would cool it better that the present LR/BR operation. Thanks for the insight.
glendodom is offline   Reply With Quote
Old 08-24-2020, 08:36 PM   #5
mtlakejim
Montana Master
 
mtlakejim's Avatar
 
Join Date: Oct 2017
Location: Bee Branch
Posts: 2,620
M.O.C. #20693
The better option is to wire the third A/C completely independent of the coach and plug it directly into the 20amp 110volt plug on the campground post. That allows you to run two A/C units at a 30 amp site. And it keeps the third A/C completely independent of the coach in case there is ever an issue (a bit of insurance if you have a pet that you have to leave alone on occasion).


It is not that difficult to run an independent power wire to the third A/C and out to it's own separate plug/panel on the outside. Just be sure to use an extension cord that is heavy enough from the panel to the campground post.
__________________
James & Irene Wilson
Bee Branch, AR.
2017 Ram 1 ton diesel duallyCrew Cab/Long Bed
2018 Montana High Country 381TH Garage Full of Toys
mtlakejim 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

» Featured Campgrounds

Reviews provided by

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 - 2024, vBulletin Solutions, Inc.