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


Reply
 
Thread Tools Search this Thread Display Modes
 
Old 08-21-2020, 10:22 AM   #1
The Joymobile
 
2011 22' Sport
MERIDEN , CT
Join Date: Jul 2020
Posts: 109
Dometic RM 8501 3 way fridge Use Question While Boondocking.

Recently acquired a 2011 22' Sport FB with a Dometic RM 8501 3 way fridge. We've been drycamping in a 10' 1966 canned ham with no fridge (Or furnace for that matter) for several years so the AS is a huge upgrade.

We're using the fridge now on shore power while staying in a Army Corps campground and while moochdocking at relative's homes. Seems to work fine.

I did run it for a short while on propane yesterday but not long enough to tell if it was performing properly. I'll experiment more with this after we return home.

In terms of expectations, propane seems to be the preferred cooling method while dry camping since at 11A per hour, the Dometic chews through most batteries quickly. (I have read about some impressive Solar/Lithium setups...but we're not there yet).

Questions:

Assuming no solar/lithium setup, seems like 12v then is only used for very short periods of time or when traveling, correct?

How long do two fully charged 20 lb LP tanks last, running the fridge and assuming no propane heater use? I'm thinking many days...

I know this is a 3 way fridge....one has to be the most efficient. I'm assuming 120v shore power is the most efficient and cools the best....however, I have no basis in fact.

Thanks, Jeff
JeffofCT is offline   Reply With Quote
Old 08-21-2020, 10:38 AM   #2
Rivet Master
 
2018 25' International
Slidell , Louisiana
Join Date: Sep 2017
Posts: 3,725
for the size refrigerator I'm going to use 7.4 BTU/min for heat loss. Propane has a heating value of 21,548 BTU/lb so that would have you using about half a pound per day.
BayouBiker is offline   Reply With Quote
Old 09-25-2020, 07:37 PM   #3
2 Rivet Member
 
2016 22' Sport
WALNUT CREEK , California
Join Date: Oct 2018
Posts: 99
As you noted, propane is the preferred heat source when boondocking, as battery power is a big energy user when used as the power source for the refrigerator absorption cycle. If plugged in, then 120V will work just as well.

With respect to propane usage, think in terms of months, not days for a two propane tank set up. I have a 2016 22FB with the same refrigerator and have used it 3-4 weeks at a time without running out a single bottle of propane. That includes a small amount of heater use, as well as normal hot water heating every day or two.

But don't get me started on the reliability and cooling capability of our specific Dometic absorption refrigerator. Ours has given me nothing but trouble, and after constant worry about the poor cooling and potential food spoilage, plus hours and hours spent testing and diagnosing, I am about to pull it out and go with a Danfoss compressor style refrigerator. Others have had much better luck, and as always, YMMV.
jmickow is offline   Reply With Quote
Old 09-26-2020, 02:14 PM   #4
2 Rivet Member
 
2019 19' Flying Cloud
Hillsboro , OR
Join Date: Apr 2020
Posts: 24
Dometic 3 way fridge lp performance

Quote:
Originally Posted by jmickow View Post
As you noted, propane is the preferred heat source when boondocking, as battery power is a big energy user when used as the power source for the refrigerator absorption cycle. If plugged in, then 120V will work just as well.

With respect to propane usage, think in terms of months, not days for a two propane tank set up. I have a 2016 22FB with the same refrigerator and have used it 3-4 weeks at a time without running out a single bottle of propane. That includes a small amount of heater use, as well as normal hot water heating every day or two.

But don't get me started on the reliability and cooling capability of our specific Dometic absorption refrigerator. Ours has given me nothing but trouble, and after constant worry about the poor cooling and potential food spoilage, plus hours and hours spent testing and diagnosing, I am about to pull it out and go with a Danfoss compressor style refrigerator. Others have had much better luck, and as always, YMMV.
Just got back from a 3 day boondock trip, our first, using a Honda 2200 LP conversion generator for back up. We have the 2019 16' Bambi with original lead acid battery. I plugged into the generator upon first arriving at the site to charge up the battery and get the refer adequately cooled. Ran the generator for 3 hours assuming that the battery was sufficiently charged and the refer was sufficiently cooled - which it was - ice was froozen. At this time I switched the refer to gas use only and after turning the refer off and on 4 times, I THINK the refer fired up. To confirm this, I pulled the exterior vent cover off to listen if the burner was fired up and it was. We went for a two hour walk and checked on the refer upon return and the ice was melting and it felt less cool. Check in the morning and the refer was obviously not cooling and through the night could hear the lighter of the refer clicking throughout the night. Also, the water pump struggled to operate and the lights were noticeably dim. We used headlamps all evening.
In the morning, I plugged into the generator for 3 hours and switched the refer to shore power mode to get things cool again. Unplugged and turned on the water pump and it seemed to struggle to run - like it wasn't getting enough power to operate effectively. What do you all think is the issue(s)??
CRRVP is offline   Reply With Quote
Old 09-26-2020, 03:26 PM   #5
Site Team
 
azflycaster's Avatar

 
2002 25' Safari
Dewey , Arizona
Join Date: Mar 2005
Posts: 15,615
Images: 62
Blog Entries: 1
Quote:
Originally Posted by CRRVP View Post
Just got back from a 3 day boondock trip, our first, using a Honda 2200 LP conversion generator for back up. We have the 2019 16' Bambi with original lead acid battery. I plugged into the generator upon first arriving at the site to charge up the battery and get the refer adequately cooled. Ran the generator for 3 hours assuming that the battery was sufficiently charged and the refer was sufficiently cooled - which it was - ice was froozen. At this time I switched the refer to gas use only and after turning the refer off and on 4 times, I THINK the refer fired up. To confirm this, I pulled the exterior vent cover off to listen if the burner was fired up and it was. We went for a two hour walk and checked on the refer upon return and the ice was melting and it felt less cool. Check in the morning and the refer was obviously not cooling and through the night could hear the lighter of the refer clicking throughout the night. Also, the water pump struggled to operate and the lights were noticeably dim. We used headlamps all evening.
In the morning, I plugged into the generator for 3 hours and switched the refer to shore power mode to get things cool again. Unplugged and turned on the water pump and it seemed to struggle to run - like it wasn't getting enough power to operate effectively. What do you all think is the issue(s)??
Sounds like your battery is not lasting very long. Monitoring the 12 volts would be your first step in problem determination. If you do not have a digital multi meter, get one.
__________________

Richard

Wally Byam Airstream Club 7513
azflycaster is offline   Reply With Quote
Old 09-26-2020, 09:37 PM   #6
2 Rivet Member
 
2016 22' Sport
WALNUT CREEK , California
Join Date: Oct 2018
Posts: 99
If you have an Airstream with the SeeLevel monitor, then you can use that as a rudimentary battery voltage monitor. You should check to see what the voltage is when fully charged after you run the refrigerator, and then keep tabs on what it says when you are having problems. I grabbed this from another post which shows how to interpret the voltage readings of the battery, whether from a voltmeter or the SeeLevel monitor:
Attached Thumbnails
Click image for larger version

Name:	Battery Voltage.png
Views:	64
Size:	204.4 KB
ID:	379565  
jmickow is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Inverter use while boondocking THMiller Batteries, Univolts, Converters & Inverters 43 06-22-2019 06:57 AM
Can I use my refrigerator while boondocking? Funster Boondocking 12 05-04-2019 11:03 AM
Dometic fridge fan running while fridge is off fclewis Electrical - Systems, Generators, Batteries & Solar 4 10-17-2018 08:30 PM
Dometic 8501 Question DDickey Refrigerators 0 07-20-2017 12:09 PM
Making a 2-way Fridge into a 3-way Fridge? Bunkroom Refrigerators 18 06-03-2014 04:37 PM


Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.



All times are GMT -6. The time now is 11:33 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.