Over Thanksgiving weekend we went camping in the California desert with some friends, It was getting pretty darn cold at night and we flipped on the heater and it flipped itself off. It was never able to ignite and we got by borrowing extra blankets. The heater had failed this way several years ago and I took it to an RV repair shop to get it going again. ...don't remember what they did unfortunately. This time Cary explained that a likely cause was a failure of the "sail switch" due to the battery being a little weak and suggested I install a device they made to boost the voltage to the fan so tghat it would flip the switch. I got it, installed it and it worked and so did the heater. Well, it worked in my driveway anyway but not last week camping in Yosemite where it left me cold.
All that was to explain why I would like to replace this heater with a different and hopefully better one. I only use the thing a few times a year but I don't need one that only works when it is warm. Has anyone replaced the propane heater with a different model?
I am an RV tech, and spend more time working on these furnaces than I care to admit. The Suburban heater is actually pretty reliable as a whole, the problem is they don't get cleaned.
The sail switch is definitely one of the more troublesome components. I see a lot of dirt that collects on the paddle and in the switch area itself -- 9 times out of 10 the switch is just fouled and needs attention. They also will get a little 'weak' but that takes some time -- the switch usually makes a nice solid 'click' and they get mushy. I suggest only using factory switches - you can buy them on amazon, but like everything on Amazon, is the quality the same? I'd rather spend a few dollars more.
As for the thermostat, they work the same way in RVs -- which is different than home furnaces. In general (there may be some new chinese companies doing things different, I havn't seen them yet) Suburban and Dometic work the same way. 4 wires. Red and black and two blue wires. The red and black are 12 volt power supply. The two blue are the control wires that go to the thermostat.
These two wires go directly from the furnace to the t-stat. All the C.I. thermostat is, is a bimetalic strip that closes a little contact when it gets too cool -- then opens when it warms. SUPER simple and far far more reliable than anything with a keypad. RV Thermostats as I said are not compatible with home furnace thermostats or vise versa. They work completely differently and on different voltages. Save the headache, and stick to the small mechanical one that Campinn installs. Its a Suburban 161154 and sells for about $22 online
If your furnace is turning on randomy the two blue wires are shorting out -- quite possibly in the thermostat itself.
Hello, our heater didn’t operate as expected on our last trip to the coast (November). The thermostat we have in #1010 looks, uh, not good. We are thinking to swap it out. What kind did you end up buying?
As for the thermostat, they work the same way in RVs -- which is different than home furnaces. In general (there may be some new chinese companies doing things different, I haven't seen them yet) Suburban and Demotic work the same way. 4 wires come out of the furnace itself. Red and black and two blue wires. The red and black are 12 volt power supply. The two blue are the control wires that go to the thermostat. Touch the wires together and the furnace should start. So, if your furnace is randomly starting -- its in the thermostat wires.
These two blue wires go directly from the furnace to the t-stat. All the C.I. thermostat is, is a bimetalic strip that closes a little contact when it gets too cool -- then opens when it warms. SUPER simple and far far more reliable than anything with a keypad. RV Thermostats as I said are not compatible with home furnace thermostats or vise versa. They work completely differently and on different voltages. Save the headache, and stick to the small mechanical one that Camping installs. Its a Suburban 161154 and sells for about $22 online
If your furnace is turning on randomly the two blue wires are shorting out, and possibly the thermostat itself.
If you insist on a new digital thermostat, you need to think about getting power and ground to it, I havn't pulled mine apart, I assume C.I. only pulls two wires to it. Honestly the digital thermostats aren't any better.
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The way furnaces work is that they always get 12 volt and ignite when the two blue wires are contacted, and shut down when the two blue wires are disconnected. Really simple. The 'cycle' goes something like this:
1] Ask for heat thruogh thermostat (which closes the 2 wires)
2] The main board will check the safety circuit making sure the sail switch is "open" proving that it is 'working' -- a sail switch that is stuck closed will make the furnace act as if it is not working -- no blowers, no sounds.
3] Once the safety circuit is verified, the Main board will then turn on the blower motor and watches the sail switch which should close in just a second or two.
3a] At all times it is watching for the sail switch to "open" indicating a blower fault. There is also an overheat device called an ECO (emergency cut off) that will turn off the furnace in the event of an overheat. These are also non terribly uncommon --- I carry an assortment of them on my truck at all times.
4] After a time delay of about 15 seconds, this time is used to purge any unburned propane that MIGHT be in the chamber. Safety again. Assuming you have propane, you may here a tic-tic-tic as the furnace tries to ignite. Noramlly it ignites on the first attempt and you just hear a 'woosh' as the burner starts.....you'll notice heat coming from the ducts in a few moments.
5] Once temperature is reached, the thermostat senses the right temperature, it turns off the swtich to those 2 blue wires. The gas will be cut off, and the blower will run for 30 seconds or so cooling things off. The furnace goes to sleep, waiting for the thermostat to ask for heat again.
If you hear tic-tic-tic but there is no woosh, check your propane supply. A low tank and cold temperatures will mean teh furnace is working fine, there just isn't enough propane. If you hear tic-tic-tic and no light, the furnace will wait a few seconds and try again. 3 times. If it doesn't ignite on the 3'rd attempt, it will 'lock out' -- you need to turn the thermostat all the way to 'off' then back on again. If heat is called, go back to step 1.
Propane: Propane boils at -44 degrees. This is how propane turns from liquid to gas, just like water to steam. So, the lower the temperature the less enthusiastic the conversion to a gas is, and, the less propane you have the less vigorous it is. So full takes and warm temperatures are needed.
Always check your propane first. The best way to check it is to just turn on the tank. I've gotten to a couple of 'repairs' to fix things by simply turning on the valve. I like to turn my valve to about 1/2 to 3/4 of the way open. You don't need to turn it to the 'full stop' open. In fact, that can cause damage to the valve body. There's also some safety advantages to it. Turn of the valve to just snug --- "kung-fu" grip tight is not needed.
But, to test if the valve is open is to simply pour a little warm water over the tank --- then try to light the furnace. If it starts, you're low on propane and its too cold. Here's how we were told to 'remember' that. Where do you get warm water at 2am? Easy. Its a campground. No judgement zone right? Pee on it

-- That's enough 'warm' to make it boil enough to start the furnace --- not for long mind you, but you can at least determine you don't need my services -- you are just low on fuel.
Hopefully some one gets some benefit from this.