stove "whines" when primary air is closed

[joustinghill]

Hi all,

I have a weird question and I couldn't find an answer to it using the search function. I have a 1991 Avalon 996E plate steel stove installed with a full liner into an existing flue (half-in/half-out of the fireplace). The procedure we've come up with for using it with the least amount of effort is "wait until the temperature has dropped below the useful point, fully reload stove, open primary entirely until temperature is back up to just above where I want it to cruise, then close primary air" This has worked great for us for the few months we've owned it.

Two days ago, the stove started making a weird whining sound when I close the primary air. It'll whine for a good 5 or 10 minutes, and then stop. Cracking the primary back open just a touch will also make it stop, but then the temperature keeps climbing. In all other respects the stove behaves as it always has.

Could this be related to the excessive cold spell we're having, or have I probably broken something in my stove? If so, where should I start looking?

Thanks for your help!

 

[Slow1]

I wonder if perhaps more cold give you more draft, thus when you shut down the primary air you essentially have greater suction being created until things normalize. This suction is pulling air into the stove through some small space (gap, crack in a seal, perhaps the primary air doesn't quite close all the way, perhaps secondary air holes shape, etc) at a high velocity creating turbulence at a frequency that you are hearing. Once the flue cools a bit and suction normalizes (i.e. draft reduces a little) the speed of air through whatever gap goes down and the pitch of the turbulence changes or goes away so you no longer hear it.

If the reason isn't the cold spell causing increased draft, the same basic theory could apply if you have a new air leak somewhere that is just opening up. I have noticed different sounds when I first close my system down after getting things roaring as the pressures stabilize.

Just a theory - could all be bunk. Get what you pay for

 

[stejus]

My new Hampton HI300 does this from time to time. This morning the stove top was at 225. I loaded her up with small splits (n/s and e/w orientation) and let her burn hard for about 15 minutes. The stove top temp was at about 275 and I started to back down the air because I was concerned with over-firing. As soon as a notched the air down about an 1", she started to whistle. I waited five minutes and notched her down another 1". After 10 minutes or so, the whistle went away and the secondary was burning hot.

 

[Jay777]

I have the same thing. It's worse when it's windy, and it doesn't happen with the draft open, only when it's at least half closed. Not sure if there's anything I can do about it, but it's pretty annoying. It *usually* goes away after 2-10 minutes, but sometimes it just keeps whining. It's always done this, so it's not related to the extreme cold, at least not for me.

And with a big gust of wind, it makes the noise even with no fire going.

I'd love to hear a solution if there is one. The pitch is constant, btw.

 

[DAKSY]

I have the same thing. It's worse when it's windy, and it doesn't happen with the draft open, only when it's at least half closed. Not sure if there's anything I can do about it, but it's pretty annoying. It *usually* goes away after 2-10 minutes, but sometimes it just keeps whining. It's always done this, so it's not related to the extreme cold, at least not for me.

And with a big gust of wind, it makes the noise even with no fire going.

I'd love to hear a solution if there is one. The pitch is constant, btw.

Pull your blower unit off. Behind it, on the right side, below the ash lip, there's a rectangular slot, about 3-3/4" high x 1-1/2" wide.
Look inside the slot. Up near the top you'll see a 3/8" diameter hole...It's EXACTLY opposite where your air control shaft is...
This is known as an EPA hole - where SOME of the combustion air comes in when you shut it "completely" down.
This hole wil sometimes create a harmonic as air is sucked thru it...
You can try putting a piece of aluminum tape over it or filling it with RTV.
Sometimes, you'll get a "whistle" thru it even when you're not burning...
HTH

 

[Jay777]

Well, that's certainly the sort of thing that would explain it.. But if I tape over it, wouldn't that have a negative impact on my secondary burn?

(also, is RTV high-temp silicone? Is it durable enough to put *inside* a stove like that?)

Thanks!

 

[DAKSY]

But if I tape over it, wouldn't that have a negative impact on my secondary burn?

Not completely...that's why I posted that it would reduce SOME of the air in. The fix was recommended from FPI (Regency) tech

also, is RTV high-temp silicone? Is it durable enough to put *inside* a stove like that?

RTV is a hi temp & should hold up...If not, put a 3/8' stubby bolt in there...or a piece of fibregla insulation or kaowool or rockwool