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Ask Dave: My RV’s refrigerator won’t turn on when using battery power. Why?

Dear Dave,
My fridge will not turn on when using battery power. What am I doing wrong? —Mark, 2015 Winnebago View

Dear Mark,
According to the specs on the Winnebago site, your View has a two-door Norcold refrigerator. So I assume it is an absorption refrigerator that operates off 120-volt power or LP.

How an RV fridge is designed to operate

To best answer the question, we need to look at how the refrigerator is designed to operate. When plugged into shoreline power and the refrigerator is on “auto,” it is designed to use a heating element to boil the rich solution of ammonia, hydrogen, water, and sodium chromate. I won’t go into the entire operation, rather the main sources of heat operation. Even when plugged into shoreline power, the 12-volt house batteries supply power to the thermistor as well as the main setting board we call the “eyebrow” board.

When the shoreline power is not plugged in or there is no 120-volt power to the refrigerator, the “auto” mode automatically switches to propane mode. A flame heats the rich solution instead of the heating element. This operation requires 12-volt house battery power to open the gas valve, spark, and to the eyebrow board.

From my sources at Winnebago, the View came standard with a 2-way absorption refrigerator and does not have a battery mode, which would be a 3-way and have a 12-volt heating element as well. Both Norcold and Dometic stopped building a 3-way model in the larger units back in the mid-1980s, as they did not cool much more than leaving the door shut and drained the batteries quickly.

Why an RV’s fridge wouldn’t turn on when using battery power

So, there are a few scenarios with your fridge not working on “battery power.” If you are not connected to shoreline power but are trying to run the unit on the LP mode, then the first thing I would do is check the voltage at your battery bank and then at the refrigerator. You can do this at the module board on the back of the refrigerator. This is the black box to the left, just under the cooling unit coils.

Check the batteries

If you have good power at the battery bank and nothing at the refrigerator, check to make sure the battery disconnect switch is off, meaning the batteries are connected. You should be able to verify this by turning on a light inside.

If you have 12-volt battery power elsewhere in the rig and not to the refrigerator, check the 12-volt circuit breaker, typically in an upper cabinet. Winnebago typically uses push-in circuit breakers vs. the automotive plug-in type.

Next, check the fuses in the module board on the back of the refrigerator and you should be able to track down where there is a loss of 12-volt power.

One last scenario

On the off chance you do have a 3-way refrigerator that is designed to work on 12-volt power, I would first check your house battery bank to verify 12.6 volts, then turn the refrigerator on to the 12-volt mode and see what the voltage of the battery is. If they are sulfated and they drop at initial start, the refrigerator will not work as it needs 11 volts to operate. When you are connected to shoreline power, your converter will charge the batteries at 13.8 volts and then maintain at 13.2 volts. If your batteries are sulfated, the converter will provide continuous power to run the 12-volt functions of your rig. If the battery bank drops, you know it’s the batteries. Not the batteries? Then check the voltage at the module board and to the heating element.

If this all checks out, you should be able to check the heating element with an ohm meter. However, if everything checks out to that point and the heating element is not hot, you won’t need an ohm meter to tell you the problem. Sometimes the element is weak and just doesn’t heat well enough. There should be some info on ohm readings in your owner’s and service manual from Norcold.

Dave Solberg is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club.

Read more from Dave here

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Steve
1 month ago

To me, it sounded like the question was why it wouldn’t work when they were on battery power and not on shore power.

KBowden
1 month ago

Like others, my first thought was that the propane supply may be turned off. Our unit, on auto, will start a beeping alarm if the gas isn’t available when the shore power is removed.

Don
1 month ago

A third possibility is that propane isn’t reaching the refer. In my 2005 Class C I had to light the stove burners to pull the propane from the line. Once the burners lit (and I turned them off), the refer would kick on. This was needed whether I was on shore power or not.

Tommy Molnar
1 month ago

Thanks for explaining why we don’t SEE any of these 3-way fridges. I always wondered about that.

Charlie Sullivan
1 month ago
Reply to  Tommy Molnar

That’s interesting. We have a 2013 LTV that came new with a 3-way Dometic refrigerator. It has worked flawlessly and cools very well since we first got the RV. Now I’m hearing this refrigerator was discontinued in the 80’s…interesting!

Tommy Molnar
1 month ago

That IS interesting!

John Goodell
1 month ago

When I received my Montana 5th wheel, the 2-way refrigerator would only cool when connected to shore power, even though it was receiving 12v power, had a good propane flame, and everything else checked out. I searched and searched for the reason. Finally I saw a manual that listed a ‘baffle’ above the propane flame which was missing from my unit (Norcold 618111 Wire Baffle). This baffle collects heat from the flame and concentrates it in order to boil the coolant solution. I installed the baffle and the problem was solved. It was like a miracle.

Thomas D
1 month ago

I really think they expect the refer to run on 12 volt only. Like dave said they quit making them. You won’t want one anyway. They kill the batteries quick.
Clarify your expectations and go from there. I think Dave explained this well.

Bob p
1 month ago
Reply to  Thomas D

I had a 3 way fridge in my ‘78 TEC Camp Mate TT that was wonderful traveling because the truck kept the battery charged, no need to travel with gas on. People abused what they were designed for and thought they could boondock and use 12V for running the fridge. I don’t believe manufacturers ever designed it for camping purposes, it was for traveling.

Eric
1 month ago
Reply to  Bob p

Very good point.

TIM MCRAE
1 month ago

Check if you have propane in the tank and if it is on!

Make sure the fridge is set to auto or LP

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