whistle from Suburban Furnace not fan

[emery395]

Our 2017 cyclone's furnace makes a whistling sound a minute or two after starting up. The whistle is not coming from the fan because it stops during the cool down cycle and the fan is still running. I'm assuming therefore the noise is coming from the flaming unit.

Any ideas of cause and fix? Thanks in advance.

 

[jerryjay11]

could be you gas supply valve or dirty burners. You can google to get more info.

 

[emery395]

Thanks Jerry.

I also meant to ask in this thread if there are return ducts to the furnace and if so where might they be located on this model 4005?

 

[cookie]

Typically the return air is nothing more than a slotted panel that could be located high or low somewhere in your coach.
Like under a refrigerator or stove.
There is no actual return ducting.

Peace
Dave

 

[emery395]

SOLVED
suspected burner fan but not the case.
Turned out to be propane auto switchover valve. I had turned it to just point to one tank instead of pointing to middle where it could function automatically. When I put it back at middle position the noise stopped

 

[Kristin44]

SOLVED
suspected burner fan but not the case.
Turned out to be propane auto switchover valve. I had turned it to just point to one tank instead of pointing to middle where it could function automatically. When I put it back at middle position the noise stopped

Thank you! Saved us a sleepless night, that noise started at 11:30pm. I found your comment and sent him out to try it and bam! Fixed! Thank you so much! 🤗