Fuse blows when switched to 12v fridge.

[Caper43]

Can someone give any ideas why my battery fuse blows when I put the fridge on 12v? No issues with fridge on 120v and propane. Would like to keep the fridge going when we are on the road. Any help would be great.

[bikendan]

Originally Posted by Caper43

Can someone give any ideas why my battery fuse blows when I put the fridge on 12v? No issues with fridge on 120v and propane. Would like to keep the fridge going when we are on the road. Any help would be great.

Why not run it on propane, when on the road, until you figure it out?

[5picker]

Has it ever worked on 12v?
Have you done any tests with a multimeter?

As Dan mentioned, just run it on LP until you get it figured out.

[Scrapper]

Originally Posted by Caper43

Can someone give any ideas why my battery fuse blows when I put the fridge on 12v? No issues with fridge on 120v and propane. Would like to keep the fridge going when we are on the road. Any help would be great.

We need more information such as what is the make and model of your refrigerator.

If your refrigerator is a 3-way you could have a short in the 12vdc heater circuit.

Most refrigerators operate on 120vac or propane with 12vdc as the power for the control board and gas valve.

[Caper43]

The fridge has never worked on 12v since I have owned which has been two years. I thought running fridge on propane was a no no? The fridge is a Dometic RM 2193. I just put a new battery in the trailer as the old one was useless. Fridge operates by gas, 12v dc or 120v ac.

[5picker]

Originally Posted by Caper43

The fridge has never worked on 12v since I have owned which has been two years. I thought running fridge on propane was a no no? The fridge is a Dometic RM 2193. I just put a new battery in the trailer as the old one was useless. Fridge operates by gas, 12v dc or 120v ac.

Depends on who you ask. Some folks wear tin foil hats too.

These appliances are made with the option to be operated on LP as you go down the road.

Only YOU can decide.

Since your model does not have a 12v control board (manual controls) you are going to have to trace the 12v circuitry from the fuse to the refrigerator and see if it is shorted anywhere.

If that's OK you'll need to test the 12v switch and the 12v heating element.

[Flybob]

What size fuse?

[Caper43]

Fuse size in there now is 10amp.

[bikendan]

Originally Posted by Caper43

The fridge has never worked on 12v since I have owned which has been two years. I thought running fridge on propane was a no no?

As was said, there are some that have fears on about this.
But propane-capable fridges have been running in RVs for decades. And for those that have them, the vast majority have no problems running them on propane, while traveling.
Since the majority of RV fridges are 2-way, using the propane side is the only way to run it while traveling.

[GlennW]

I had a 2193 fridge in my camper and had issues with the propane flame blowing out on the road. So I ran a 110V extension cord from the fridge compartment (drilled a hole in the floor) and ran it far enough to be inside the tow vehicle where I plugged it into a cheap 400W Inverter that could be plugged into the lighter socket. The fridge plug had to be moved from the wall socket inside the fridge compartment to the extension for traveling.

Why? Because the 12V on the 2193 isn't controlled by the thermostat but the 110V is, so even if you do get the fridge working on 12V (it draws over 10 amps) then fridge could get too cold if you are traveling in cool weather. At 110v, the current is less than 2 amps so wire size isn't important. This worked very well for me but you may have to limit the lighter socket to powering just the fridge.

As well, on the 2193, the thermostat doesn't control the propane flame. You just have low, Medium and High so 110V is always preferred.

Glenn

[UT_Grandpa]

A 10 amp fuse is only good for about 120 Watts. I think the heaters pull more than that. Before replacing with a larger fuse make sure your wire feed to the fridge is 14 GA minimum with 12 GA preferred. Remember, the fuse is there to protect the WIRE not the device.

When we had a PUP, we ran the fridge on propane while towing all the time. BUT in the presence of flammable liquids (gas station) the fire needs to be turned off. Our current TT has a circuit that will relight the flame if it blows out so again, we travel on propane. Arriving with a full battery is important and most tow vehicles can not pass enough current through the plug to do much good.

[denville]

FUSE
A 12 amp (continuous rating) fuse should be incorporated in the wiring of the DC supply, as near to the battery
as possible. The fuse must be in the side of the wiring
which is not connected to the chassis. For example, if
the vehicle has a negative ground, the fuse must be in
the positive side of the wiring

.
11.12 VOLT DC CONNECTION
The 125 watt heating element operates the cooling unit
when the refrigerator is connected to the battery of the
vehicle. It has a current rating of about 10.5 amps: therefore, the wiring from the battery to the refrigerator must
be of heavy enough gauge to carry this load satisfactorily without undue voltage drop. To ensure this, the minimum size of wire to be used is 14 A.W.G. The terminal
block for connecting the 12V supply cable to the battery
is positioned at the lower lefthand corner of the rear side
(G, FIG. 8). From this terminal, the connection to the
battery should be made using ring-type clamps with
tightening bolts to ensure good contact with the battery
terminals. Polarity is not important, therefore it does not
matter which wire leads to which battery terminal.

[Caper43]

Originally Posted by UT_Grandpa

A 10 amp fuse is only good for about 120 Watts. I think the heaters pull more than that. Before replacing with a larger fuse make sure your wire feed to the fridge is 14 GA minimum with 12 GA preferred. Remember, the fuse is there to protect the WIRE not the device.

When we had a PUP, we ran the fridge on propane while towing all the time. BUT in the presence of flammable liquids (gas station) the fire needs to be turned off. Our current TT has a circuit that will relight the flame if it blows out so again, we travel on propane. Arriving with a full battery is important and most tow vehicles can not pass enough current through the plug to do much good.

So on the return trip home I upgraded the fuse to 20amp and it worked fine. Wiring seems to be up to standards, so I took the chance. Happy it’s working now and thanks for the replies.

[babock]

Most of the time, these are actually 30A fuses on Dometic.

[pgandw]

Originally Posted by Caper43

So on the return trip home I upgraded the fuse to 20amp and it worked fine. Wiring seems to be up to standards, so I took the chance. Happy it’s working now and thanks for the replies.

Ideally, should be a 15 amp fuse to protect wiring and fridge. That's what is on the DC side for my A-frame fridge, and is appropriate for 14 gauge wiring.

Glad to hear the problem was simply a fuse too small.

Fred W
2019 Flagstaff T21TBHW A-frame
2008 Hyundai Entourage minivan
camping Colorado and adjacent states one weekend at a time

[Scrapper]

Caper43, do you have the owners manual?
If not here's the manual and parts list.

[Caper43]

Originally Posted by Scrapper

Caper43, do you have the owners manual?
If not here's the manual and parts list.

Thanks for the manuals!