New 2023 2600RB Heater running constantly

[Laktah]

We recently picked up our RV and it was a bit chilly so we decided to turn on the heater. During the night the outside temp dropped to 40-45 F and the heater in RV seemed to run almost constantly with temp set to 70. The fan would come on and then the flame would ignite for 45-60 seconds, then flame out while fan still ran. It may Flame on again a time or two, or the fan will eventually turn off. It would only stay off for 45-60 seconds then the process would repeat. Is this a normal operation for the GD 2600RB heater? Very annoying for sleeping for sure. Once again this is a brand new 2023 2600RB.

[howson]

Laktah -- noted that was your first post, so welcome to the forum. Check out the New Members letter when you get a chance.

To your question--no, that's not normal. One of the symptoms of a furnace ...that seems to run continuously in an effort to satisfy the thermostat ... is a lack of return air. (Quote from Suburban RV Furnaces Service & Training Manual.)

According to a diagram I have access to view, the return air path is under the stove (the furnace is in the corner between the sink and stove). Is something blocking the return air from getting to the furnace?

Howard

[familytruckster4]

As Howson says it may be something blocking the return air or it may be something blocking the movement of air from the furnace. The symptoms you describe could be an upper limit switch shutting the furnace down due to excessive heat in the furnace itself. If thats the case a blockage or some construction debris may be blocking one or more of the outlets.
Personally, unless its something obvious and easily remedied I would let my dealer worry about fixing it. If the dealer does work on it I would advise you to test it when picking it up to make certain they actually worked on it and remedied the issue. (I have a very dim view of dealers and their ability to actually fix problems)

[Guest]

We recently picked up our RV and it was a bit chilly so we decided to turn on the heater. During the night the outside temp dropped to 40-45 F and the heater in RV seemed to run almost constantly with temp set to 70. The fan would come on and then the flame would ignite for 45-60 seconds, then flame out while fan still ran. It may Flame on again a time or two, or the fan will eventually turn off. It would only stay off for 45-60 seconds then the process would repeat. Is this a normal operation for the GD 2600RB heater? Very annoying for sleeping for sure. Once again this is a brand new 2023 2600RB.

The furnace could be going into overtemp. Or a lack of battery power to keep the system running. When there is a call for heat, the fan will start which is a dual function fan. One side circulates air inside the rig and the other side operates exhaust gases. They are separate in their function even though they operate off the same motor. On the circulation side there is a sail switch that is closed during airflow and will allow the gas valve to turn on and the igniter to operate. This is the sequence of operation.
When the furnace shuts down, it most likely due to the overtemp sensor being defective, or there is actual overtemp due to the lack of airflow through the furnace to keep the heat exchanger in the normal temperature range. There could also be a voltage drop situation if the battery or converter is having issues.
I would start with a basic inspection of the air ducts as Howard stated and then electrical check, then a gas pressure check and pressure drop test on airflow. A manometer is used to do these last two tests.

Jim