Furnace question

[JohnDolyn]

My Atwood 8940 furnace seems to be cycling on the furnace temp limit. I can hear the burner come on, run for a while and shut off, the fan continues to run, a few minutes later the burner comes back on. This continues until the thermostat is satisfied, at which time the system shuts down. Does anyone have any suggestions as to where to look for the cause of this burner action? I do seem to have air flow at the floor registers.
Thanks for any help.

[walt2137]

Sounds like your thermostat is real close to the heater out put and causing it to cycle, try to shield it someway.

[Stillwater]

Mine was doing that as well. I found that two of the output duct hoses was right in front of the intake air blocking a good part of it. It has improved but still will cycle some. I think the thermostat hasn't got enough range between starting and stopping the furnace. It does the same with the air conditioner. Maybe someone knows if that can be adjusted or a better thermostat to use.

[pipedream2]

You furnace is operating as it should.Once the burner starts the high temperature limit switch on the heat exchanger controls the burner..on and off as need as long as the thermistat is not satisfied.Once the thermostat is satisfied the burner stays off and the limit switch will shut down the blower when cool enough.
the only thing that will affect the burner on/off cycle is air restriction across the heat exchanger allowing it to get too hot.maybe a dust vacumn out is in order or restricted air intake (return air inside of coach....the outside vents are combustion air only) in front of frdige...if its under there