TC Refrigerator blows 30 amp fuse in truck

[BudDugly]

I have a 2005 Lance truck camper with a 3-way refrigerator. I've tried using the DC setting twice and both times it caused a 30 amp fuse to blow in my truck's fuse box. It seems I read somewhere that a larger wire may need to be run from the truck to the camper. Any ideas about that?

[billtex]

BudDugly wrote:
I have a 2005 Lance truck camper with a 3-way refrigerator. I've tried using the DC setting twice and both times it caused a 30 amp fuse to blow in my truck's fuse box. It seems I read somewhere that a larger wire may need to be run from the truck to the camper. Any ideas about that?

One idea; run on propane.

[Kayteg1]

My neighbour in California lost her million dollar house due bad connection in power outlet.
Make it 2 neighbours, but the 2nd was couple of blocks away and my wife knew her from school meetings.
Nothing is bulletproof, but propane fires usually go with big boom.
Go figure.

[bigfootford]

Kayteg1 wrote:
Excess Flow Devices are mounted only on cylinders and they come to the market about 15 years ago. Older RVs with propane tanks still run without such things.
You concluded well that it was a fire that totaled RV, but still that would never happen would propane be turned off at the tank.
The safety subject has thousands of topics on the forum and the "it never happen to me" replies are not changing my mind.
I consider TC being much safer in this situation than other type of RV so did not worry about it so far, but finding better solution is still on my mind.

Many rv fridge fires were started by the fridge running on 12vdc.

I will not get into an argument about the subject but anyone who wants to really know about 12vdc issues with fridges... just keep reading and go to the links I have provided.

Just look at this picture and notice that the ground connection of the power cord is gone!
A clue, go the links I am providing for some reading on the subject.



I have studied the issue extensively wrote about it a few times, worked on one TC that nearly burned up... So here is some reading:

https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/20474425/srt/pa/pging/1/page/1

https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/19726244/srt/pa/pging/1/page/1

Go down in the page of this thread and note my discussion and measurements on Sleepy's nor cold fridge...

https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/23706949/srt/pa/pging/1/page/2.cfm

If you have read all of these you should have read about the Norcold rep removing the harness and left. The rig owner could not take more pictures for me.

I turned this whole thing over to the NTSB... Two times... No answers....

Since all this took place nearly 10 years ago I still attempt to look at any fridge fire I have seen...

Some looked like the fire started at the power cord...

Another thing to think about, most RV'ers are not RV.net members...

I see rv's that have burned up all the time when traveling over the years. Our camper has almost 200,000 miles on it so we have seen lots of RV carnage not all fires but more that I would like to see....

Jim

[Kayteg1]

Excess Flow Devices are mounted only on cylinders and they come to the market about 15 years ago. Older RVs with propane tanks still run without such things.
You concluded well that it was a fire that totaled RV, but still that would never happen would propane be turned off at the tank.
The safety subject has thousands of topics on the forum and the "it never happen to me" replies are not changing my mind.
I consider TC being much safer in this situation than other type of RV so did not worry about it so far, but finding better solution is still on my mind.

[Old-Biscuit]

Kayteg1 wrote:
I like the electric power while on the road for safety reasons.
Even the fridge open flame is on other side than my fuel door, my discomfort for driving with open propane valve come from motorhomes, where lot of total losses were due flat tire rupturing propane line mounted on top of inner fender.
Point is that standard 30 amp wire has too much voltage loss on the length those wires run and even when you start with fully charged camper battery, after some driving the refrigerator will drain it.
Other thing is that 12V operation is on smaller output, while I camp in very hot weather and good cooling is crucial.
So this is my winter project to either run heavy 12V wires to the camper, or having factory inverter in my Ford - I might run 120V wire just for the refrigerator.
The problem with 2nd option is that when I stop the truck, what kills inverter, the fridge circuit will try to ignite propane.

Those 'total loss' MHs were most likely due to fire but NOT from the propane line busting.
Propane system has 'Excess Flow Devices' that trip and limit flow should line/fitting break
Fire was likely due to brakes/oil catching on fire

[Kayteg1]

I like the electric power while on the road for safety reasons.
Even the fridge open flame is on other side than my fuel door, my discomfort for driving with open propane valve come from motorhomes, where lot of total losses were due flat tire rupturing propane line mounted on top of inner fender.
Point is that standard 30 amp wire has too much voltage loss on the length those wires run and even when you start with fully charged camper battery, after some driving the refrigerator will drain it.
Other thing is that 12V operation is on smaller output, while I camp in very hot weather and good cooling is crucial.
So this is my winter project to either run heavy 12V wires to the camper, or having factory inverter in my Ford - I might run 120V wire just for the refrigerator.
The problem with 2nd option is that when I stop the truck, what kills inverter, the fridge circuit will try to ignite propane.

[work2much]

Using the chassis starter battery to power the camper isn't a good idea. You should consider installing an isolator between your truck and the TC. This will allow the truck to charge the camper batteries but won't allow the camper to drain the truck battery.

As others have mentioned using the battery to run the heating element in your ammonia absorption fridge requires a substantial amount of continuos power. We often run our fridge through our battery/inverter and our battery monitor tells me that it takes over 30Ah DC to do so. Given the distance and wire size from your starter battery to the fridge I suspect a large voltage drop exacerbating this issue.

Unless you have a large battery bank, and means to keep it charged (more than the trickle charge from running the truck) you are better off using propane.

[bigfootford]

KD4UPL wrote:
Your truck's charge fuse isn't supplying just the DC refrigerator. It's also trying to charge the TC batteries and power the LP leak detector, CO detector, stereo memory, TV amp, and whatever else.
Refrigerators use so much current on DC that's is kind of a useless option unless you significantly upgrade the circuit from the truck all the way back. I've always found it was much easier to just run the fridge on propane. I never used the 12v setting. The propane used is minuscule.

Exactly!

[KD4UPL]

Your truck's charge fuse isn't supplying just the DC refrigerator. It's also trying to charge the TC batteries and power the LP leak detector, CO detector, stereo memory, TV amp, and whatever else.
Refrigerators use so much current on DC that's is kind of a useless option unless you significantly upgrade the circuit from the truck all the way back. I've always found it was much easier to just run the fridge on propane. I never used the 12v setting. The propane used is minuscule.

[Old-Biscuit]

What size DC heater element fuse is on the fridge circuit board?
Most with a DC heater use a 30A auto style fuse


DC heater elements are 115W to 275W (10A to 23A)

Exactly which 30A fuse in truck fuse panel is blowing...what is it labeled for?
Fridge DC should have nothing to do with blowing truck fuse.

[Kayteg1]

Each refrigerator has label saying the power draw in each mode.
12V draw is usually in 15-20 amp range, so unless you have bigger than usual refrigerator, something else has to be wrong.

[pianotuna]

My fridge on DC draws between 34 and 36 amps.

I suggest adding a 2nd charging path direction from the starter battery to the "house" jars and using wire appropriate for 50 amps with a 50 amp automatic circuit breaker.

[Lwiddis]

One post is sufficient.