As most RV’ers are aware…the absorption type refers that come with RVs can possibly start a major RV fire as they operate with a hydrogen and ammonia mixture of chemicals. Fires started by them are the #2 cause of RVs being totaled out by insurance companies. Engine fires are #1 reason. Often the owner is driving at freeway speeds when they notice smoke pouring from the outside refer vent. By then, it’s too late to do much to save the RV.
If the owners are the type to go to the beach, come back home, empty the refer and shut it off, the average is 7 years before it develops a leak. These are often harmless leaks as the chemicals exhaust into the unheated space behind the refer into the atmosphere through the venting on the outside and roof of the RV. Usually the owner won’t know about it until they get ready for their next trip, they open the freezer and smell ammonia, or they see a yellow residue on the coils.
Sometimes, however, the leak develops when driving the RV and this can be very dangerous as the refer auto-switches to an open flame gas heating system for cooling while driving. Preventing this is pretty simple as the refer can just be switched off from the inside control panel, and used during a days trip with limited opening and closing of the door. Suppressing the urge to open/close more than twice during a days drive is the best way. And then switch it back on as soon as you’ve parked for the night or, like I do, an hour before arriving. It only takes a bit of habit forming to deal with it. Even during hot weather, I’ve found the refer stays cool enough that things haven’t warmed up much when I arrive at an RV park.
Leaks turning into a fire can also happen when parked, for instance if the owner has set the refer for gas only. The best thing to do is keep the refer on AC all the time, as this keeps the coils warm all the time, which prevents moisture from creating small rust spots which can turn into leaks. If that’s not possible, it’s best if the owner is a seaside beach enthusiast to carefully and gently rinse off the coils on the back of the refer when they get home, turn power back on quickly and keep it powered until it’s dry, then finally shut it down for the duration. It doesn’t take much battery power to keep it powered when using gas, so as long as the engine is started every 5 days or so, the refer can run on batteries. It’s best and most convenient that it’s plugged into power though. Salt from sea air is highly corrosive to the metal coils, which is why I suggest rinsing off the coils when storing the RV. If you live at the seashore, best to keep the refer powered all the time. You can easily get 25 years from an absorption refer in an RV if you are careful. My last absorption refer was still working fine after 12 years of handling it as mentioned above, spending months at a time at the seashore, and my current refer is now 20 years old, and because it was rarely used by the original owners, I expect at least another 10 years out of it.
With that background in mind, this article is about preventing too much damage if the refer does develop a leak and you perhaps forget to shut it off while driving, or if it’s on gas when parked, perhaps when boondocking. There are a couple after market systems that cost a couple thousand that are available to extinguish a refer fire once it’s started, and those are fine. But I feel they are a bit overkill as the millions of RVs out on the road seldom have a refer fire. Odds are against it ever happening. But being safe has it’s advantages.
So in order to be safe I’ve taken a somewhat different approach with mine. And what I did instead of installing a fire suppression system was to buy and install this nifty mini Car Fire Extinguisher. It is compact, is triggered by heat, and will leave little residue if ever triggered.
The above is an Amazon advertising trade picture and if it’s copyright then it’ll disappear when a web crawler finds it. But that link to the Amazon ad will remain so check it out.
Here’s how it is packaged. I wrote the install date, and the fact that it was good for 10 years in black marker on the side of it’s case. Plenty of room on the body of this extinguisher to do that too. Then I covered that with packing tape so it won’t fade over the years. It’s palm sized.
Nice little device just right for this vent space behind the refer on the outside of the RV.
I mounted it up on the inside of the outside wall. First I cleaned off the mounting area with a shop rag, checked for dirt and grime where I planned on placing it, then stuck it on with the provided 3M tape.
Here it is mounted and just peeking over the upper edge of the compartment’s opening.
And a close up. Smile!
The device will blow out a chemical mixture from the holes in the package in a high speed cloud towards the right in this picture. I angled it this way because those holes are not supposed to be too close to anything that might block it and that was the best way to mount it in this situation with my RV so as to avoid blocking it. Most refer fires start in and around this area, I’ve studied the pictures of RVs in salvage yards so I think this will work well if a fire ever occurs inside this compartment. Plus I can see it easily when I remove the cover…and so could any potential buyer if I sell this rig.
So for $40, as opposed to between $1200 to $2600 for a professionally installed refer fire extinguisher system, I’m willing to accept some danger to save $1160. I hope to never see smoke of any sort exhausted from this vent area when driving, and if I do, I have my fingers crossed that this little extinguisher will give me enough leeway to pull off the road and stop so there’s no road wind whipping any flames around as this device should have extinguished any fire. And should give me time to grab my big extinguisher as backup.