Damper Questions

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Glenwood MWP

New Member
Oct 27, 2015
7
South Coast Massachusetts
Let me start by thanking you all for all the great advice and info I have gathered as a "lurker" on this forum. It has been invaluable! So I'm breaking down and finally asking a question. I have a restored Glenwood Modern Wood Parlor #220 that was installed with two dampers 12" apart on the advise of the restorer/installer. currently the lower damper is located-8" above the top of the stove and 11" above the exhaust elbow. This stove exhausts out the upper rear into a 90d elbow. I am planning on reconfiguring the pipe to make sweeping and cleaning a little easier. Does any one have any advice on minimum height of the lower damper from either the rear elbow or top of the stove? I'm not sure which is more critical. I have seen 6" inches from top mentioned on the forum, but I'm not sure if that's the same for a rear exhaust stove. Thanks guys.
 
Is this connected to an exceptionally tall chimney? If not I would try running it with a single damper at 12-18" above the stove top.
 
It is not overly tall. My goal was to remove a small section of cut pipe he put in to make it all fit. By doing so I would be lowering the damper. The 12" you recommend as a minimum is close to where it is now so I may leave well enough alone.
 
Normally in the first straight pipe. The farther away from stove, the cooler and more soot blocks the regulated air holes when closed. The closer to stove the hotter to touch. Antique dampers have better regulation closed compared to newer dampers with little to no flow when closed. The new ones clog easy with very little air space at damper rod. Did the person who recommended two know what type chimney, flue size, and connector pipe configuration? The damper isn't for the stove, it's for controlling the chimney.
If you have an insulated flue the same size as stove outlet, that produces the strongest draft. Connector pipe length, elbows and fittings reduce draft. The damper is a variable resistance to reduce more when necessary. Like a valve in a water line, it will reduce the same no matter where it's located.
 
It's a double wall pipe through the ceiling/roof only. Same I.D. Throughout. They are defiantly antique dampers. Currently I have about 30" of straight vertical pipe after the 90d elbow out of the stove back then two 90d elbows connected, then about 72" to the ceiling. The plan is to have 24" off the first 90d change the other 2 90s to 45s and add a telescoping pipe length into the 72" run. Going by your account the only drawback to lowering the dampers is temp to the touch. I think I'm Ok with that as currently I wear gloves when adjusting them anyhow.
 
I was able to get a hold of the restorer and had him come by to check out my refit. The lower damper ended up 7" off the top of the exhaust elbow and 4" off the stove top. He felt that was good to go. Thanks all.
 
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