A/c fire

[jdickson18]

My fifth wheel burned last night starting in the roof top Coleman a/c that was not turned on. Has anyone ever heard of anything simaliar happening? One of the controls must have shorted for this to have happened.

[CLIFFTALL]

Welcome to irv2. Sorry to hear about your 5th wheel. Hopefully everyone's ok. I've not heard of this happening before .

Cliff

[94-Newmar]

Jdickson, Sorry to hear about your loss.

Can you post the year/make/model of your 5th?
Do your roof A/Cs have the on/off/temp controls in the ceiling at the air outlet or on a wall mounted thermostat?

In either type of setup there is still 120v live (if plugged into shore or, if equipped, on generator) inside them even if the A/Cs are turned off. Wiring is generally ran into a junction box of some sort. There could be a dozen reasons as to what caused this.

There is a strain relief that is used to tighten down against the wiring where it enters the junction box. This is to prevent it from being pulled out and in some cases those can be tightened down too far causing the wire insulation to be cut or compromised in some fashion and over time can short itself.

Did the fire dept have any ideas?

[jdickson18]

Originally Posted by 94-Newmar

Jdickson, Sorry to hear about your loss.

Can you post the year/make/model of your 5th?
Do your roof A/Cs have the on/off/temp controls in the ceiling at the air outlet or on a wall mounted thermostat?

In either type of setup there is still 120v live (if plugged into shore or, if equipped, on generator) inside them even if the A/Cs are turned off. Wiring is generally ran into a junction box of some sort. There could be a dozen reasons as to what caused this.

There is a strain relief that is used to tighten down against the wiring where it enters the junction box. This is to prevent it from being pulled out and in some cases those can be tightened down too far causing the wire insulation to be cut or compromised in some fashion and over time can short itself.

Did the fire dept have any ideas?

Hi, Thanks for the prompt replies. It's a 1994 Carriage Carri-lite Cashay. Roof mounted a/c controlled by a wall mounted thermostat. I agree that there is 110 power to the a/c when plugged in to shore power. Puzzled by the fact the the breaker did not trip if it did short at the connection clamp. Insurance inspector has not been out to see it yet.

[TXiceman]

Sorry to hear about the loss. One thing that happens to ALL RVs is things loosen over time. I make a yearly inspection of all water, drain piping and electrical connections once a year. Running down the road causes a lot of vibration and any connection can loosen.

A loose electrical connection will have a higher resistance and will get hot. It can get hot enough to cause a fire.

I have never heard of an A/C unit catching fire as you described. A capacitor can blow and cause a fire as well.

ken

[anotherone]

if your camper insurance doesn't cover contents your homeowners will. You will be surprised at how much we stick in out campers. Dont take insurance company first offer. Research on internet the value of your camper and print out documentation on everyone of them you can find. Take the 10 highest prices and send them to the adjuster. Also remember to not be in a hurry. If they find that there is a known defect in the unit they will go after the manufacturer to get their money back and your deductible too! This is major PIA but what is ,is. Been there and still dealing with it. NORCOLD .

[wa8yxm]

Has anyone ever heard....

Yes... Rare but I have heard of it. There are several ways it can happen.

Method 1: The power lines into the unit have been rubbing against something for however long it has been since the unit was built the insulation has rubbed off and as a result arching and overheating of wires has happened.

Method 2: Rodents have camped out inside and nibbled the wires leading to method 1.

The solution: Periodic inspection and cleaning.

How long has it been since you popped the top (Pulled the cover off) and cleaned and inspected.. NOTE you usually need to pull some inner covers as well.

Method 3 (Sadly the solution does not apply to this one)

Control system failure leading to arcing of the compressor or blower relay and .. Well we have covered the effects of arcing already.. There is a solution for this too but it takes a whole lot more training.

[jdickson18]

Thank you to all that have replied I did go and inspect the camper myself yesterday and found it was not the ac that started on fire it was the refrigerator. When my friend first noticed the flames they were coming out of the roof around the a/c. Looks like the refrigerator ignited the wall behind it, melted all of the aluminum frame, then went across the ceiling and the found it way out around the a/c. Research has proven refrigerators are one of the primary causes of fires in campers. It was running.

[94-Newmar]

Ouch. I would certainly like to see pics of the cooling unit if you have any available.

[jesilvas]

Wonder if it had the recall installed.

Was it level?

[homeless]

howdy! It cant be the A/C the only thing that catches fire on an RV is the Nor cold refrigerator...

[CLIFFTALL]

Originally Posted by jesilvas

Wonder if it had the recall installed. Was it level?

Wrong cooling unit . This thread is about a roof top ac unit.

[anotherone]

Originally Posted by Clifftall

Wrong cooling unit . This thread is about a roof top ac unit.

the op just clarified and said it was the refer instead of the ac

[CLIFFTALL]

Originally Posted by anotherone

the op just clarified and said it was the refer instead of the ac

Oops. Thank you. I missed that post .