[GMCnet] Dometic fridge drains battery

[Nelson Wright]

My Dometic 2 way fridge is draining the house battery in about 10 hours when in the gas mode.
I have isolated it from every thing else by turning it off and monitoring the battery condition for a 24 hour period. all is well until I turn on the fridge and then the battery will discharge in about 10 hours.I have checked the interior light switch and gave the battery a load test. Next step?

Nelson Wright
Belle Isle Fl.
78 Royale Rear Bath
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[Justin Brady]

Put your multi meter in current mode and see what it's pulling from the battery.
It should pull very little current, under an amp I would imagine, when in gas mode.

--
Justin Brady
http://www.thegmcrv.com/
1976 Palm Beach 455

[Nelson Wright]

If i am reading this cheap HF multimeter correctly it indicates .55 amp and goes to 1.15 when I open the door with the interior light on

Nelson Wright
78 Royale rear bath
Belle Isle Fl

[John R. Lebetski]

Can you give more info on the battery load test and age and type of battery.
--
John Lebetski
Woodstock, IL
77 Eleganza II

[Nelson Wright]

It's a 3yr old Bosch series 65 1000 ca and tested with a resistance type load meter.
BTW I also got the same results when connected to the start battery.
I am about to hook it up to a new stand alone battery just to eliminate the bad battery possibility.

Nelson Wright
78 royale
Belle isle Fl

[Rob Mueller]

There's nothing wrong with your Dometic fridge, it uses 12VDC power to sense
the temperature in the fridge and regulate the flow of LPG to the absorbtion
chilling unit.

Regards,
Rob M.
The Pedantic Mechanic
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808

[poww...@gmail.com]

Nelson,
As with all VOM to read the current the meter must be connected in series with load. With the HF Cen-Tech digital meter you must also move the red lead to the 10ADC plug in on the meter. The 4 ma to 25 ma scale(upper right corner) would not let you get reading in the range you have indicated. From a little over .55 amp to 1.5 amp should not deplete your battery in the time you indicated. I have run my Dometic frig on gas for 4 to 5+ days before the battery or the gas ran out. As suggested by others I would do a load test on the battery or batteries if using dual 6 VDC batteries, I would suggest using a battery hygrometer and check the specific gravity of the battery acid to determine if you have a dead cell. Depending on what type battery charger you have and how old the batterie(s) are could determine battery life. I get 8 years out of set of 6 VDC batteries typically and the single 12 VDC batteries have been know to not last much over 3 years.

Regards,

J.R. Wright
GMC GreatLaker
Newsletter Editor/Publisher
Tech Editor
78 Buskirk 30' Stretch
75 Avion Under Reconstruction
Michigan

[Justin Brady]

That sounds right on the amp draw.
I'd say you're looking at a battery issue.
With just a small 100ah battery you would be looking at 150+ hours to drain it completely with the fridge running.

--
Justin Brady
http://www.thegmcrv.com/
1976 Palm Beach 455

[Ken Burton]

I found on some web site that the 12 volt current draw should vary between .5 and 1.2 amps. So your numbers look fine.

I would be looking at why the battery is not being charged or not holding a charge.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Nelson Wright]

OK, doing what JR suggested with the meter I now I find that it starts out at 4.3 V load but after about 30 seconds it jumps to 6.3 V. Open the door and it jumps to 11.2 V. Test is being done with the refrigerator isolated to a car battery. Other than this current drain the refrigerator is working fine.


Sent from my iPhone
Nelson Wright

Orlando Fl.

[Nelson Wright]

Ken,
The battery is being charged and holds a charge on till the refrigerator comes online. this would be in the dry camping mode of operation when there is no battery charging going on.

Sent from my iPhone
Nelson Wright

Orlando Fl.

> On Mar 15, 2017, at 2:49 PM, Ken Burton <n9...@comcast.net> wrote:
>

[Johnny Bridges via Gmclist]

"starts out at 4.3 V load but after about 30 seconds it jumps to 6.3 V. Open the door and it jumps to 11.2 V. Test is being done with the refrigerator
isolated to a car battery. Other than this current drain the refrigerator is working fine."

Something is rotten in Denmark :) If we're looking at current draw, we won't measure it in volts. And the meter connection will be different to
measure voltage and current. If you were measuring voltage across something connected in line with the icebox, this set of readings would be
consistent with a gas icebox. First we'd see the current drain of the ignitor, then that of the controls and valve system, and finally the additive
draw of the interior light.
However, every indication so far is that your icebox is working correctly. It runs on 11AC or propane, but not on DC alone, correct? (DC alone would
flatten the battery overnight). JUst for fun, what's the exact model number of the Dometic?

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased

[Nelson Wright]

Johnny,
The model number is the RM2820 end it is a two-way 120 AC and propane. And looking for the model number I discovered that there is a humidity switch which was turned on. I turned it off and now getting a reading of 3.5 A which is still to much draw I think .
And yes I do know the difference between volts and amps but this old age thing it's catching up with me🙁

Sent from my iPhone
Nelson Wright

Orlando Fl.

[Ken Henderson]

Nelson,

With a Google search, I found this on an Avion site:
-----------------------------------------------------------------
JIm, the owners manual for my Dometic RM2820 does not address DC current
draw. So today I put the AVION in boondocking mode and let it run all
afternoon. The current draw when the flame comes on starts out at about 330
ma and as the solenoid coil heats up, the draw drops to near 300 ma. When
there's no flame, the draw is about 80 ma.
-----------------------------------------------------------------
Which tallies with the notion that your 3.5A draw is abnormal.

None of the Dometic manuals I looked at has any clue about a possible
cause. TIme to call Dometic support. In the past I've found them
helpful. Even sent me a new control board when the only problem with the
old one was that the blown LED-monitored fuse had blown, leaving just
enough current flow to drive my voltmeter. :-(

Good luck,

Ken H.

[Nelson Wright]

Ken,
Thanks for the information. I am going to monitor the battery drain overnight now that I have turned off the humidity switch and see where I stand. Also I am not sure if I am reading the multimeter correctly.
Good to know that the support people are helpful, as I may give them a call tomorrow.
Thanks to everyone for your support and I will keep you informed.

Sent from my iPhone
Nelson Wright

Orlando Fl.

[Johnny Bridges via Gmclist]

Welcome to Age Makes Strange Answers club :) However, I don't think the trouble is with the icebox - although I've no idea what the humidity switch
is. Whatever it is, I'd expect the current to go up when it's on and down when it's off. Three and a half amps might be enough to pull a sketchy
battery down overnight.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased

[Emery Stora]

The humidity switch warms a heating tape located around the door so as to keep condensation off the edge of the door.

Emery Stora

[Ken Burton]

Nelson wrote on Wed, 15 March 2017 14:48

> OK, doing what JR suggested with the meter I now I find that it starts out at 4.3 V load but after about 30 seconds it jumps to 6.3 V. Open the
> door and it jumps to 11.2 V. Test is being done with the refrigerator isolated to a car battery. Other than this current drain the refrigerator is
> working fine.
>
>
> Sent from my iPhone
> Nelson Wright
>
> Orlando Fl.

None of these numbers are making sense to me. Are you measuring amps or volts? Are you connecting the meter in series with the +12 volt (or ground
lead) lead feeding the refrigerator? Or are you measuring voltage across something? Where exactly are you connecting the meter?

[Nelson Wright]

Ken,
As I admitted to Johnny I had a senior moment when I stated volts while measuring amps. The meter was in series between the positive battery post and the fridge contact.
Also while looking for the model # I discovered a humidity switch that was energized and contributing to the power drain.

Nelson

[Ken Burton]

Ok, I'll go re-read it and substitute amps for volts and then I'll probably understand it.

[Ken Burton]

Your numbers seem to be off by a factor of 10. Are you sure that you are not reading a decimal point incorrectly, or do not have the meter set to a
scale where it is times 10?