Harmonic roaring furnace

[pittendrigh]

I have a relatively new Energy Star Triangle Tube furnace--efficient enough the exhaust pipe is a 6" inch PVC pipe. Or is it 4" inches? Hot water radiator system.

Everything works well except one problem. This furnace make a trombone like roaring note when it starts up, that the neighbors are complaining about. Sounds a bit like a harmonic note from a guitar, crossed with a tuba.

Is this because of some odd frequency to an internal fan? Or what? Can it be fixed? My plumber has gone out of business and disappeared.

 

[havasu]

Bump for help please?

 

[Mr_David]

WOW almost 3 months old. How did this one get bye?

I have seen commercial water heaters ROAR a little.
But not so load as to cause complaints from neighbors.
how may BTU's is the furnace rated for.
what size is the gas connector.
I have often seen high BTU furnaces connected with flexible gas connectors and they whistle very load due to the high flow of gas flowing through them.
We always hard pipe high BTU units to prevent this.
Natural or propane?
Might need to check you gas pressure. need special type of gauge for that.