Barometric damper & magnehelic gauge

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jnfount

New Member
Mar 10, 2022
8
L@k3Huds0n
I am installing Drolet Heat Commander into the lower portion of a garage and heating the upstairs living space of 1440 SF. I am trying to find out which barometric damper to use, and how to use one, as well as a magnehelic gauge. 24' of double wall insulated pipe and double wall black pipe from the furnace to the ceiling.
 
And just find a good deal on a Dwyer Mark II model 25 manometer...works great for this purpose...many times you can find good deals on NOS on fleabay
 
And just find a good deal on a Dwyer Mark II model 25 manometer...works great for this purpose...many times you can find good deals on NOS on fleabay
Awesome! I was hoping you would respond. Will this fit on black double wall chimney pipe? I will plan on having to 45 degree elbows connected to a telescoping double wall black pipe to account for the offset from the back of the furnace to where the chimney goes through the ceiling.
 
Awesome! I was hoping you would respond. Will this fit on black double wall chimney pipe? I will plan on having to 45 degree elbows connected to a telescoping double wall black pipe to account for the offset from the back of the furnace to where the chimney goes through the ceiling.
Ah, yes...you did say doublewall...if I recall correctly it takes a little work to make it fit doublewall...I feel like there was someone here that pulled it off though. Certainly wouldn't work with telescoping though.
Maybe you could come off the furnace with singlewall and then convert after the baro?
 
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I run the 0.25" WC magnehelic, it works very well. Stainless tube into hot chimney, and transition to high-temp rubber tube closer to the gauge.

But I don't think you want to run a barometric damper on a wood stove, assuming you're talking about a device that allows fresh (room temperature) air into the chimney.
 
But I don't think you want to run a barometric damper on a wood stove,
Its a computer controlled whole house wood furnace...and a baro is recommended to control draft on tall chimneys...Kuuma even includes the above linked baro with the furnace purchase.
IIRC Drolet calls for -0.04 to -0.06" WC on the HC...and -0.08" WC is considered overdraft
 
Some info at the following post (link below), which I was planning to post anyways, but seeing your question prompted me to go ahead and post sooner rather than later. I know nothing about the Drolet but after my past experience with a standard US type baro damper on a wood gasification boiler (ejected fine fly ash galore), I do not want to "try" the US type baro damper again.

On gauges to measure draft, if you can find a Bacharach MZF (just corrected typo, I'd typed MZT but the gauge is MZF) it is a nice unit. Used to be a standard part of the Bacharach "Wet Kit" that was, until the arrival of electronic combustion analyzers, 'the way', for several generations, that the pros checked and dialed in oil burners and other combustion. Probably crazy expensive new, if it is even sold new, but you might be able to find a used one.

My KW baro damper info:
 
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Some info at the following post (link below), which I was planning to post anyways, but seeing your question prompted me to go ahead and post sooner rather than later. I know nothing about the Drolet but after my past experience with a standard US type baro damper on a wood gasification boiler (ejected fine fly ash galore), I do not want to "try" the US type baro damper again.

On gauges to measure draft, if you can find a Bacharach MZF (just corrected typo, I'd typed MZT but the gauge is MZF) it is a nice unit. Used to be a standard part of the Bacharach "Wet Kit" that was, until the arrival of electronic combustion analyzers, 'the way', for several generations, that the pros checked and dialed in oil burners and other combustion. Probably crazy expensive new, if it is even sold new, but you might be able to find a used one.

My KW baro damper info:
Sounds like you have a unique situation there...many many people use Fields baro's with no issue...should only ever be air going in, not flue gasses/flyash coming out. I think you will be disappointed in the results with your new baro...no such thing as a totally sealed flue system when it comes to a backpuff...smoke/flyash will find a way out.
I think you will still have the same issues...possibly to a lesser degree though...maybe.
If I were in your shoes I would be trying to figure out why the boiler is backpuffing, that's the real issue here.
 
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Ah, yes...you did say doublewall...if I recall correctly it takes a little work to make it fit doublewall...I feel like there was someone here that pulled it off though. Certainly wouldn't work with telescoping though.
Maybe you could come off the furnace with singlewall and then convert after the baro?
I will have to look into this, as I placed the furnace to have clearances for a double wall pipe. I will check to see if I can move it and still have room. Do you think clearances would be fine if I used single wall from just the back of the furnace outlet, a 90 or couple of 45's for my offset to line up with the chimney off the wall?

Is this also a good product? I could use this in between the double wall sections.
 
I will have to look into this, as I placed the furnace to have clearances for a double wall pipe. I will check to see if I can move it and still have room. Do you think clearances would be fine if I used single wall from just the back of the furnace outlet, a 90 or couple of 45's for my offset to line up with the chimney off the wall?

Is this also a good product? I could use this in between the double wall sections.
I could also get this. Do you think I can put a baro damper in this T fitting?

 
Do you think clearances would be fine if I used single wall from just the back of the furnace outlet, a 90 or couple of 45's for my offset to line up with the chimney off the wall?
Depends...do you have a pic...or drawing of it?
Is this also a good product? I could use this in between the double wall sections.
Yes on both...but not sure those will fit into doublewall? Might just have to try it and see...
 
The T from menards is already a double wall. IF I can fit the baro into it and it will work properly, I will go that route.
Different brands of pipe don't always work the best together...but that's not to say that it couldn't be made to work.
I guess when you get the baro take it to the store and try it in the tee since it appears that they stock them. Did you get all your pipe and chimney there? I've had good luck with the Selkirk/Supervent stuff.
 
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Different brands of pipe don't always work the best together...but that's not to say that it couldn't be made to work.
I guess when you get the baro take it to the store and try it in the tee since it appears that they stock them. Did you get all your pipe and chimney there? I've had good luck with the Selkirk/Supervent stuff.
I got all the black pipe and fittings from Menards. They are 3 hours away from me, so I will probably just order all the pipe and fittings I need and then order a baro and see if it fits. Are all the baros about the same ? Or is the field controls a tried and true one?