Suburban Model SF-30FQ

[2015 Outback 323BH]

Hey guys I have an Outback 323BH with the Suburban Model SF-30FQ. I have had intermediate problems with the furnaces since we got it in 2015. What happens is it will blow for 30 sec and shut off.


I have propane I can run everything on propane in the camper they all work. I have replace the regulator just in case.

When I turn the thermostat on you hear the click at the thermostat and then the blower comes on. It will run for 30 sec and shut off.

If I pull the unit out of the camper and bench test it with the 12 volte battery from the camper it works find. Now keep in mind I'm not running propane to it but you turn it on it blows for 15 sec and then you hear the click of the gas valve and the multiple clicks of the ignitor. Then nothing but the blower and then again the click of the gas valve and the multiple clicks of the ignitor and then again same thing after 15 sec and then the unit will shut down.

Put it back in the camper and it might work for a day or two and then the same thing the unit shuts down sometime in the night and will not re light blows for 30 sec no click of the gas valve and it will not start till I pull it out of the camper test it on a bench and it works. :banghead:

I the ducks are not clogged in the camper so I don't think I'm hitting the over limit switch I don't have a thermostat problem because the bower motor starts right away when I turn it off and back on. I have replaced the sail switch but I think the old one was fine I tested it with a meter. Still the same problem it has been in the dealership 4 times all they have done is replace the gas valve and tell me it's working I get it home and it does the same thing.

I am at a lose here guys Please help.

[flybouy]

Have you checked for sufficient voltage at the furnace while it's installed? Checked for good grounding as well? By bench testing with the battery from the camper I'm assuming you have "jumper wires" from battery to furnace. This would eliminate all the wiring in the camper, so that's the first thing I'd check. Next I'd check for the other difference between in the camper and on the bench and that would be any obstructions in the combustion air and exhaust or flue gas for obstructions such as mice nest, mud daubers nest, bees nest, etc.

[chuckster57]

You need to bench test with regulated propane supply. I suspect the igniter, sensor or control board.

[JRTJH]

Possibly a thermostat problem. I'd first check it by turning the thermostat up to about 85F or so, turn it to heat and see what happens. If it works, it's the thermostat. If it doesn't, I'd suspect an electrical connection problem or the control board. Start by checking ALL wiring going to the furnace for any loose or corroded connections, make sure the fuse socke.ts are clean and secure (no loose fitting fuse blades) and that there is 13.6VDC at the control board. If that's good, then I'd replace the control board.

My recommendation is a Dinosaur Electronics board rather than an OEM board. They seem to be more reliable, better built and usually less expensive.

[2015 Outback 323BH]

Wires are good I have 13.5 volts at the wires going to the unit. I have a board on order it will be here tomorrow.

All three vents are blowing well. Bunk house, living room and bed room.

[2015 Outback 323BH]

Hey Guys just an update I replaced the controller on the unit it's been running fine for the past 3 days. I did buy a new thermostat its digital not analog like the original.

[RobK]

Hey Guys just an update I replaced the controller on the unit it's been running fine for the past 3 days. I did buy a new thermostat its digital not analog like the original.
What model digital thermostat did you replace your old one with?