All about RV electrical fires and a new way to extinguish them fast


By Mike Sokol
Hey, everyone. You know me as the RV Electricity guy, but I am indeed interested in all sorts of things, including those that can be dangerous to an RVer.

But before I go on, can we please agree on one thing: safety. I believe safety should be the most important thing on our minds when we buy and use a recreational vehicle, how we pack it for trips, how fast we drive, and where we park. After all, I think we can all agree that we want our family and friends to be safe.

And if there’s anything we can do to improve the safety of our loved ones, then it’s worth discussing.

With that in mind, I was sent a link to an Airstream trailer fire that occurred last weekend. I’ve been in contact with the owner who has agreed to let me post these pictures of a fire that totally destroyed his trailer in just a few minutes.

While it’s too early to know exactly how the fire occurred, there’s evidence that it was in or near the 3-way refrigerator compartment. And since the propane was turned off and the trailer was plugged into shore power, there’s a real possibility this was an electrical fire. Now, we need to put a pin in this particular story for now because I haven’t yet seen the insurance report. But as soon as I get enough information I’ll publish the complete story in my RV Electricity Newsletter the last Sunday in June.

What is an electrical fire?
In the meantime, let’s discuss exactly what an electrical fire is and a few ways we could possibly prevent one. In the first place, these are not fires made of electricity. The electricity simply provides the ignition source, either through resistive heating which can result from a space heater or an overheated wire, a direct flame such as a propane cook top, an electrical spark from a wire with failed insulation, or a loose screw in a connector.

Next we need a combustible material, which our RVs have in abundance. Even something like an aluminum body Airstream has a wooden floor. But even aluminum will melt and burn if the fire gets hot enough.

Finally, we need a source of oxygen, which happens to be all around us. It doesn’t take much beyond the three elements of oxygen, combustible material and a spark or hot surface to start a fire. And when it begins, any RV basically becomes a blowtorch with the fire consuming it in a matter of minutes.

What can we do to help prevent this sort of tragedy?

Well, there is a recent technology that’s supposed to be required in all new RVs being built after 2020. It’s called an AFCI for Arc Fault Circuit Interrupter, and you may already have it in your own home, especially the bedroom of a house that been built in the last 10 years. The job of the AFCI is similar to the GFCI (Ground Fault Circuit Interrupter), except for instead of looking for a fault current going through your own body and heart, it’s listening for any sparking noises in the wiring which could indicate a wire with compromised insulation, or perhaps a loose screw that could be sparking. And just like its cousin the GFCI, it shuts down the power to the circuit before it can start a fire. According to, “In the United States, arcing faults cause more than 30,000 home fires each year, resulting in hundreds of deaths and injuries.”

In a nutshell, ACFIs have been required in new residential home construction (for bedrooms) since the 2009 NEC (National Electrical Code) was adopted, and it will probably be required in all new RV construction with the adoption of the 2020 NEC.

Okay, so enough about electrical fires that start from sparks. How about fires that start from direct overheating or even a flame source?

Is there a technology that can stop a fire quickly AFTER it starts? Well, indeed there is. I saw how this worked last month at the Ramblin’ Pusher Club Rally in Goshen, Indiana, and it was mighty impressive.

It’s the THIA fire suppression system from PROTENG. Basically it’s a plastic tube filled with a firefighting agent that remains liquid at normal temperatures. So there’s no nominal pressure in the tube, only liquid.

But if there’s a fire in the protected area and the tube reaches sufficient temperature, the liquid turns to gas and begins creating pressure inside the tube. And once the plastic tube gets hot enough from the hot air or direct flame, the tube ruptures and fills the area with a non-toxic fire-fighting gas, putting out the fire in a matter of seconds. Watch a short video demonstration:

I will feature both AFCI and THIA technologies in my next RV Electricity newsletter, which publishes in a couple of weeks, but I want you all to begin thinking about fire safety in your RV. To me, there are few things scarier than an RV fire, so anything you can do to protect yourself and your family from one is worth the effort. Remember, nothing is more important than the safety of you and your family.

See you next week. And in the meantime, let’s play safe out there.




  1. Pretty cool. I recently sent The Fire Guy an email asking about suppression for RV’s. Looking forward to the article. Hopefully it will have some approximate cost info and how and where to install for best overall protection.

      • I’m setting up an interview this week with Proteng and asking them all your questions. I’ll include their answers in a video, audio and text interview in my next RVelectricity newsletter. Stay tuned!

    • Prices will not be given unless you call them. They suggest that they need the area size in order to properly size the tubes. I would assume that they also need to know the heat characteristics of the area to be protected. See the FAQ area of the Proteng site:

  2. We are looking for a suitable fire suppression system to protect our 2018 diesel class A pusher. When we looked at the THIA strips, we were very impressed right up until we found out that every strip has a life of around 4 years, after which each must be replaced. As an alternative to replacing our entire fire suppression system every four years (yikes!), we are electing to install gas and foam fire suppression systems from Fire Fight Products ( that feature a lower initial cost (installed) and only need to be replaced as needed based on the reading on the discharge meters. According to Jim Bounds, the proprietor, only a few canisters over the years have required replacement (short of being discharged to put out a fire, of course); most of their gas and foam canisters last indefinitely.

  3. Big Truck Big RV guy just reported that his THIA strips have popped for no reason just because of Texas heat. He was given a bunch to promote and I was a fan of them until this latest report.

      • According to him he followed the directions, maybe they sent him the low temperature models, but he installed one in the engine compartment of his F450 truck and one in the back of the refrigerator compartment of his 5th wheel, both went off within a week with no fire.

    • Standard Units have a trip temp of 158 F.
      Heavy Duty Units are set for 194 F.

      it would not be hard to understand that on a 100 F day, an enclosed compartment could easily reach much higher temps. If the compartment is painted black (as many full body paint units may be), it would certainly raise temps even higher.

      • There is a question on the FAQ page indicating:

        Is the PROTENG® fire suppression device covered under warranty?

        Yes, we offer a one-year warranty for commercial use and two-year warranty for private use.

  4. ACFI’s have been required by the NEC since 2008 in homes (bedrooms). They may or may not work in an RV depending on how the the circuits have been wired. You would be best advised to find a qualified electrician to do the work.

    • I should preference bedrooms and all other spaces except kitchens garages unfinished basements and laundry rooms

  5. THIA? At first I thought it was spicy food. That is Protengś moniker Tube+Heat=Instant Action.

    AFCI – Not exactly new tech. Has been in NEC code since 1999 edition (initially qualified to new bedroom circuits).

    Has anybody (ie Progressive) made noises about expanding their EMS product to also be an AFDD (arc fault detection device)? While new RVs will be protected next year, there are millions that need arc fault detection and an AFCI breaker will not fit as replacement.

    • Yes, but the latest gen versions that offer combo detection have only been the last few years. And while AFCIs have been only required in bedrooms for the last 10 years, the latest code version has broadens the requirements to include even finished basement outlet and lighting circuits. RVs will be next, possibly starting next year.

  6. I work camp and mostly in maintenance. Question about the AFCI circuit breaker, will it sense arcing before it? IE; in the shore power cord or campground pedestal.

    • More to study as there are AFCI breakers offering series or parallel or combo detection. Not sure about upstream detection just yet.

  7. Hmmm … FM200 is heptafluoropropane. A liquid in normal state but turns to various gases, some of the poisonous, with a small amount of heat. In order to suppress fire an agent has to displace one of the 4 things in the fire tetrahedron. This one displaces oxygen. While it may save your rig, when your smoke detector (must have) activates …. get out!

  8. It should also be noted that the 2 Square D breakers you have in the picture might not fit in your RV electric panel, even if it is square D. My RV has a Square D panel that is very small and doesn’t have the room for Arc Fault breakers.

    • Very good point. Then, some other type of remedy should be sought, if possible. Even if changing out the entire electrical panel, if necessary. Which would be cheaper than loss of RV or lives.

    • My point was that the RV industry will have to deal with finding a way to get an AFCI to fit in an RV circuit breaker panel. Watch for the full report in my next RV Electricity Newsletter next Sunday.

      • Turning off the Power can also be helpful. My Hot Water Heater Neutral shorted out one night, smoke from melting insulation set off the Smoke Detector. I turned off the Breaker to the Water Heater (why it didn’t go off itself I’m not sure), used my Fire Extinguisher and that stopped the burning. All that was left of the Neutral Wire nut was the spiral wire.

        • The neutral shorting out to the chassis shouldn’t be able to cause a fire. Perhaps the neutral developed a loose connection and the resulting high resistance caused the wire to overheat. Can you supply more information?


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