Humming noise coming from insert?

[jhoff]

Folks, was hoping to get some feddback...

When i cut back my air flow on my insert, sometimes I hear a pretty loud humming noise. It usually lasts 1-10 minutes. It stops if I open the door. Any idea what this is and if it's a common occurance. Any safety concerns?

thanks!!

 

[Stunt Double]

I also have a regency that hums sometimes, but it seems related to temperature. I think it may have to do with the thermostat that controls the fan while it's in "auto" mode; the cooler the fireplace the less contact there is on the conectors in the switch, the less electricity goes to the fan so it hums. As the fireplace heats up, there is tighter connections in the contacts and better flow of electric.

Just a theory......

 

[Chettt]

Could it be the air pulling through the secondary holes after the primary is shut down?

 

[rdrcr56]

Our stove does it also, but if I put a gloved finger on the plate that regulates primary air flow it stops. Trying to pull mucho air through a small opening, set up a vibration?

 

[jhoff]

THX to everyone for input.

Chunk: Don't know for certain, but it seems to be tied to the primary.

rdrcr: I think you've figured it out.

 

[Lasher]

I am getting that with my Avalon Olympic insert as well. If I close down the air when the stove is cooler when starting a fire (say under 600 from my thermometer) I get the hum. Here is how I can make it stop...

1) As the stove reaches high temps, I can close the air more and more. Not sure if it ever goes away, there are times when I have the air closed and it is not there (no fan) and other times it is there. But see below on how I make it go away all the time...

2) As soon as the fan comes on, the hum stops at any air position.

My stove has two small holes on the bottom of each side. If I put my finger on the hole when the noise is happening, I can change the pitch or stop the noise. I figure that the noise is similar to blowing across the top of a bottle of soda or beer. If the hum is happening before my fan comes on, I just open the air a little. But usually the fan is blowing so no hum...

 

[James1095]

I also have a regency that hums sometimes, but it seems related to temperature. I think it may have to do with the thermostat that controls the fan while it's in "auto" mode; the cooler the fireplace the less contact there is on the conectors in the switch, the less electricity goes to the fan so it hums. As the fireplace heats up, there is tighter connections in the contacts and better flow of electric.

Just a theory......

I also have a Regency (i1200) that hums when I turn down the air, I just installed it recently so I haven't messed around much trying to locate the cause. It's definitely not the fan because I haven't installed that yet, and besides, the thermostat is a snap action bimetallic switch, it is either fully on or fully off. If the contact resistance was high enough to affect the motor performance, the contacts would burn up very quickly.

I suspect the humming may be related to the unusually strong draft I have given the flue is 22 feet of well insulated flex and the outside temperature has been quite low lately. Most of the time I have the air wide open since there's plenty of space to heat but the humming is annoying when I do turn it down.

 

[Hogwildz]

Thats the sound of a happy stove eating some air.