Furnace help plz

[howson]

Just ran across this thread as I am trying to figure out why my heater will not come on in my 2021 22RBE, this is interesting and something that I have not found or heard before. I did not know the furnace would lock out. When I try to activate my heater I hear nothing and nothing responds. Fuse is good, battery voltage is 12.3 - 12.6 when tested, propane tank is full (refrigerator works on gas as does stove and oven). I have only had the furnace on one time since I purchased and that was last year at this time. I have contacted dealer however they are 5 weeks out and I need some heat for next week as it going to be single digits in east Tennessee.
So as I understand it, I can pull the fuse and wait a few minutes before putting it back. Will this reset the heater if its locked out or do I need to remove battery cable as well.
I appreciate this information and any additional that may be shared.

Thanks,
Mark

Jlawles2 -- thanks for the tag.

Mark,
A typical Suburban furnace has what is called a "three try" board. What that means is the furnace will attempt to light three times. If the board does not sense a flame after three times it goes into lockout mode.

When the board does not sense a flame (literally a voltage level fed back from a sensor) it could be there's no flame, the sensor is not in the flame, the sensor is faulty, or the board itself is bad.

To get the furnace out of lockout all that is required is to select OFF on the thermostat, wait a moment or two, and then go back to HEAT.

As Joseph asked, if you can provide the model of the furnace and thermostat we could possibly provide more information.

Howard

[Jlawles2]

howson Thanks for the confirmation of what others told him Howard.

[howson]

howson Thanks for the confirmation of what others told him Howard.

I missed pengle's post...

[smithmr]

Jlawles2 -- thanks for the tag.

Mark,
A typical Suburban furnace has what is called a "three try" board. What that means is the furnace will attempt to light three times. If the board does not sense a flame after three times it goes into lockout mode.

When the board does not sense a flame (literally a voltage level fed back from a sensor) it could be there's no flame, the sensor is not in the flame, the sensor is faulty, or the board itself is bad.

To get the furnace out of lockout all that is required is to select OFF on the thermostat, wait a moment or two, and then go back to HEAT.

As Joseph asked, if you can provide the model of the furnace and thermostat we could possibly provide more information.

Howard

Thanks, I have a GE thermostat and unfortunately my packet has absolutely no documents for the furnace, all i know is its a Suburban 25K btu. I have no idea on the model number or anything of that sort as nothing is visible.

Its obviously not a lock out issue as it does not work after turning off and retrying even after sitting for dys in the OFF position.

I get absolutely no response from the furnace, fan or anything when attempting to turn on. From what I have read, I am thinking it is probably related to the board but i have no expertise at all in this arena.

Thanks for all the input this far.

Mark

[howson]

smithmr
If there's no response at all (fan doesn't run) there's three possibilities. Either 12vDC is not getting to the control board, the control board is bad, or a component called the "sail switch" is stuck closed.

Some resources on the forum: https://gdrvowners.com/forum/operati...ting-by-timing and https://gdrvowners.com/forum/operati...roubleshooting

Dig into those resources and you'll know more than the vast majority of owners about RV furnaces.

Howard

[smithmr]

smithmr
If there's no response at all (fan doesn't run) there's three possibilities. Either 12vDC is not getting to the control board, the control board is bad, or a component called the "sail switch" is stuck closed.

Some resources on the forum: https://gdrvowners.com/forum/operati...ting-by-timing and https://gdrvowners.com/forum/operati...roubleshooting

Dig into those resources and you'll know more than the vast majority of owners about RV furnaces.

Howard

Howard,
I can't thank you enough for your help on this. I dug into all the information and links you provided, and with that knowledge and guidance I was able to troubleshoot my way through and find the issue!
I did also learn my furnace is the 25Q model.
I found the sail switch and confirmed it was working with a multi meter.
Found the set screw holding the furnace in the housing was not in place and the furnace was not secured.... clue #1
Then checked for power and was not getting power at all. Upon tracing that issue we found the red wire had vibrated loose from the control board. It was hard to reach with furnace in place but was finally able to get an extended needle nose plier to reach the connector and got it connected. Viola we had power and furnace now works properly!

Thank you so much again for taking the time to offer advice and help me out.
Mark

[Scott'n'Wendy]

smithmr You are well on your way to being an RV tech. Glad you got it sorted!