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 > MONTANA OWNERS CLUB COMMUNITY > New Member Introductions
Click Here to Login

Reply
 
Thread Tools Search this Thread Display Modes
 
Old 08-02-2017, 04:06 PM   #1
Evergreen
Established Member
 
Join Date: Jul 2017
Location: Evergreen
Posts: 15
M.O.C. #20274
Generator question

Hello, we are new owners of a Montana 380th and new members to MOC. We just returned from our first 3k mile shakedown cruise. found and repaired a factory pin plug on a front level jack that was causing various Errors however I havent had an issue since.
Question:
Our new rig is pre prepped for an Onan 5.5 kw Genset. I want to size an Onan generator to handle a full load requiring both AC units while other appliances are running. I am looking at a little larger Onan QG 6.5 Propane unit. it has the same footprint and roughly the same weight as the spec'd 5.5. my question to those who have an Onan 5.5 LP today, does the 5.5 propane unit handle both A/C units and other appliances (Microwave/TV etc.) with ease as it states on their (Onan) website? and, at what altitudes have you ran your generator? we live at 8100 ft and typically camp at 6,000 ft to 10,000 ft. knowing significant KW loss is going to take place (more so with LP gas) at said altitudes, I want to be sure I am not under sized. (I am aware that a vented retrofit will be required to support two (forklift style) horizontal tanks.)
thanks in advance for your input.
 
Evergreen is offline   Reply With Quote
Old 08-02-2017, 06:01 PM   #2
mlh
Montana Master
 
Join Date: Oct 2004
Location: Salem
Posts: 7,528
M.O.C. #2283
Each 1000 feet of elevation reduces power output 3.6%. At 10,000 feet you are down 36%. That goes for any naturally aspirated engine.
Lynwood
mlh is offline   Reply With Quote
Old 08-02-2017, 08:42 PM   #3
dieselguy
Montana Master
 
dieselguy's Avatar
 
Join Date: Feb 2005
Location: Haysville
Posts: 4,261
M.O.C. #3085
Get ready to burn some propane ... but you said you're ready for that.
dieselguy is offline   Reply With Quote
Old 08-02-2017, 11:39 PM   #4
scottz
Site Team
 
scottz's Avatar
 
Join Date: Apr 2017
Location: Colorado Rockies
Posts: 1,910
M.O.C. #19755
I can't say that I have tried to run all of those things at the same time; I know my 5.5Kw will handle both AC units. We frequently camp at 11k; the last time we used the generator and ran one AC unit and the mircowave; did not try the second AC.
__________________
Scott & Alta
2017 Montana 3160RL, Legacy, Onan 5.5Kw, Solar
2022 F-450 Lariat Ultimate
scottz is offline   Reply With Quote
Old 08-03-2017, 05:28 AM   #5
Evergreen
Established Member
 
Join Date: Jul 2017
Location: Evergreen
Posts: 15
M.O.C. #20274
Quote:
Originally Posted by scottz View Post
I can't say that I have tried to run all of those things at the same time; I know my 5.5Kw will handle both AC units. We frequently camp at 11k; the last time we used the generator and ran one AC unit and the mircowave; did not try the second AC.
Good to hear the 5.5 can handle both AC's at higher elevations.maybe I'm over thinking it. Is your Onan a propane unit? if so, is it connected to the existing LP circuit or do you have a supplemental tank dedicated to the generator?
Evergreen is offline   Reply With Quote
Old 08-03-2017, 08:48 AM   #6
scottz
Site Team
 
scottz's Avatar
 
Join Date: Apr 2017
Location: Colorado Rockies
Posts: 1,910
M.O.C. #19755
I can't say for sure if it can handle both AC's at 11k; I did not try. However, the elevation at my house is 7400; it will run both of them here.

Mine is LP connected to the existing tanks. I don't have a lot of data, but I think it will run 6+ hours on one tank.
__________________
Scott & Alta
2017 Montana 3160RL, Legacy, Onan 5.5Kw, Solar
2022 F-450 Lariat Ultimate
scottz is offline   Reply With Quote
Old 08-03-2017, 09:39 AM   #7
Evergreen
Established Member
 
Join Date: Jul 2017
Location: Evergreen
Posts: 15
M.O.C. #20274
All very helpful data Scottz, thank you very much for sharing. one last question, do you know if your Montana has 1- 15000 BTU AC/Heat Pump and 1- 13000 BTU AC or is your set up different?
Evergreen is offline   Reply With Quote
Old 08-03-2017, 09:47 AM   #8
Evergreen
Established Member
 
Join Date: Jul 2017
Location: Evergreen
Posts: 15
M.O.C. #20274
Just noticed your pups picture, we have a 6 year old chocolate lab. best dog we have ever had in our family.
Evergreen is offline   Reply With Quote
Old 08-03-2017, 02:45 PM   #9
Kenw
Established Member
 
Join Date: Apr 2017
Location: Concord
Posts: 49
M.O.C. #19636
If you decide to purchase the larger gen set please assure that the wire size from the generator to the box is big enough to handle the additional amps. Please also make sure that the transfer switch is also large enough.
Kenw is offline   Reply With Quote
Old 08-03-2017, 03:21 PM   #10
Evergreen
Established Member
 
Join Date: Jul 2017
Location: Evergreen
Posts: 15
M.O.C. #20274
Quote:
Originally Posted by Kenw View Post
If you decide to purchase the larger gen set please assure that the wire size from the generator to the box is big enough to handle the additional amps. Please also make sure that the transfer switch is also large enough.
Will do and thank you Kenw for the heads up. I will plan to take the 5th wheel straight to the Onan Generator service/supplier here in Denver and have them check wire gauge, compatibility with the prepped start/stop panel/harnes located in the coach. didn't think about the transfer switch...
great advice!
Evergreen is offline   Reply With Quote
Old 08-03-2017, 03:39 PM   #11
Evergreen
Established Member
 
Join Date: Jul 2017
Location: Evergreen
Posts: 15
M.O.C. #20274
Funny, just spoke with the Onan provider here in Denver, when I asked him about the transfer switch he paused and said I was the transfer switch. apparently they have moved away from an automatic transfer internally, simply installing a plug at the generator to run the shore power cord up to the generator. makes sense, less components to fail. no different than plugging into a 50 amp service at an RV site.
Evergreen is offline   Reply With Quote
Old 08-03-2017, 04:19 PM   #12
Kenw
Established Member
 
Join Date: Apr 2017
Location: Concord
Posts: 49
M.O.C. #19636
I had that set-up with my Fleetwood C class that I sold earlier this year, It works just great.
Kenw is offline   Reply With Quote
Old 08-03-2017, 06:17 PM   #13
mlh
Montana Master
 
Join Date: Oct 2004
Location: Salem
Posts: 7,528
M.O.C. #2283
I don't think you are over thinking this. Onan says a 5.5 will handle 2, 13500 ACs with 1100 wats left over. The gas model has 12.9 HP the LP has 10.7 HP but at 10000 feet it's down to 7 HP and I think you have a 15000 and a 13500 AC. I don't know if it will handle both at once. I would call Onan to see what they say or just go to the 6.5 and be safe.
Lynwood
mlh is offline   Reply With Quote
Old 08-03-2017, 06:50 PM   #14
mhs4771
Montana Master
 
mhs4771's Avatar
 
Join Date: Dec 2009
Location: Sebring
Posts: 3,657
M.O.C. #9969
Our 5.5 Onan will run our dual 15K AC with power left over, but didn't use it in any high altitudes.
__________________
Michelle & Ann
2018 Chevy 3500HD High Country DRW 4X4 Crew Cab w/Duramax/Allison, Formally 2010 Montana 2955RL, Now Loaded 2016 SOB, Mor/ryde IS, Disc Brakes & Pin Box, Comfort Ride Hitch, Sailun 17.5 Tires.
mhs4771 is offline   Reply With Quote
Old 08-03-2017, 07:06 PM   #15
PNW Fireguy
Montana Master
 
PNW Fireguy's Avatar
 
Join Date: Nov 2015
Location: Arlington
Posts: 1,522
M.O.C. #18081
We have the 6.5 light commercial lp Onan. I have run both AC (15k &13.5k) units, Wingard Trav'ler, two tv's (lcd) and the microwave at the same time. However we are basically at sea level. Haven't had an opportunity to run the genset at high altitude as we have always had full hookups in those areas.
__________________
SOB
2015 Volvo VNL780 D13, iShift, 32k ET air hitch, Idle Free LiFePO4 APU
16.8KWhr LiFePO4, 2.52 kw solar, 10kva Victron split phase
PNW Fireguy is offline   Reply With Quote
Old 08-03-2017, 07:19 PM   #16
twindman
Montana Master
 
twindman's Avatar
 
Join Date: Apr 2006
Location: Mesa az
Posts: 2,926
M.O.C. #5651
I would doubt you need 2 A/Cs at 11000 feet. More likely to need the furnace.
__________________

Tom and Gail
2013 Mountaineer 362
2012 Silverado 2500
twindman is offline   Reply With Quote
Old 08-03-2017, 07:29 PM   #17
Dam Worker
Montana Master
 
Join Date: Mar 2015
Location: West Richland
Posts: 1,253
M.O.C. #17164
You might check the specs of both units to see what each leg is actually putting out. The junction box on all the units with a 5500 is rated for 30 amps. There is a post of mine on the forum that gives the exact rating per leg for a 5500 which is less than thirty amps there for allowing Keystone to use the 30 amp rated junction box and 10awg wire. The 6500 might require bigger wire and a better box. Can't tell you much about the transfer switch other than mine hums quite loudly when plugged into shore power. As stated before it is supposed to be able to run both AC units with some extra left over. Better look at upgrading your tanks to at least 40's as the tanks go dry quite quickly. My connection from the generator to the 10awqpg in the junction box nearly caught fire. All the tape was burnt off and or melted along with the wire nuts. Could have been real ugly, lucky it was a metal box and it was so hot you couldn't touch it with your bare hands. Be careful whichever way you go and it wouldn't hurt to double check the installation.

Tom Marty
__________________
Dam Worker is offline   Reply With Quote
Old 08-03-2017, 07:33 PM   #18
mlh
Montana Master
 
Join Date: Oct 2004
Location: Salem
Posts: 7,528
M.O.C. #2283
Quote:
Originally Posted by twindman View Post
I would doubt you need 2 A/Cs at 11000 feet. More likely to need the furnace.
That has been my experience to. I've camped at 9200 feet in Wy in July and had frost every morning and a blizzard in September.
My Onan does have a high altitude setting on the carburetor.
Lynwood
mlh is offline   Reply With Quote
Old 08-03-2017, 08:26 PM   #19
scottz
Site Team
 
scottz's Avatar
 
Join Date: Apr 2017
Location: Colorado Rockies
Posts: 1,910
M.O.C. #19755
Quote:
Originally Posted by Evergreen View Post
All very helpful data Scottz, thank you very much for sharing. one last question, do you know if your Montana has 1- 15000 BTU AC/Heat Pump and 1- 13000 BTU AC or is your set up different?
I think both of mine are 15k BTU. Here is a shot from the build sheet:
Attached Thumbnails
Click image for larger version

Name:	HVAC.JPG
Views:	33
Size:	13.6 KB
ID:	426  
__________________
Scott & Alta
2017 Montana 3160RL, Legacy, Onan 5.5Kw, Solar
2022 F-450 Lariat Ultimate
scottz is offline   Reply With Quote
Old 08-04-2017, 10:14 AM   #20
Evergreen
Established Member
 
Join Date: Jul 2017
Location: Evergreen
Posts: 15
M.O.C. #20274
Quote:
Originally Posted by PNW Fireguy View Post
We have the 6.5 light commercial lp Onan. I have run both AC (15k &13.5k) units, Wingard Trav'ler, two tv's (lcd) and the microwave at the same time. However we are basically at sea level. Haven't had an opportunity to run the genset at high altitude as we have always had full hookups in those areas.
Great data, thank you! Im assuming your Montana had the pre packaged control panel in coach and harness's into the genset cabinet? or did they install the generator at the dealer/factory, or, did you have it done after market?
Evergreen 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 02:56 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.