Confused by Manometer - changes when door is open vs closed

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Bigeejakes

Member
Dec 8, 2019
13
MI
Hi Guys - so i've been running a englander 28-4000 for a couple of years and have a pretty good handle on how everything is running, and I'm getting it to produce great heat with around a 6 hour burn. I have been getting quite a bit of black crystal creosote, I would say 3-4 cups 2x per year on cleanings.

Setup as you go up the chimney: Stove- Manometer inserted (6" above stove) - Manual Pipe damper - Condar Probe thermometer - 90* elbow, 4ft horizontal through the masonry wall to T and then 28' insulated stainless liner through outside masonry chimney.

Manometer is a dwyer mark II, connected by 1/4" copper tubing (no connectors, just a hole drilled in the pipe and tube snugly fit.

Here's the goofy thing: My draft readings are running in the -.10 to -.15 range when the door is closed and no pipe damper being used (when stove is at operating temp... and if I open the door at that stage, I get a -.05 to -.07 reading. SO it seems that by closing the door it causes my draft readings to increase by about 2x.

Which one do I use? Based on how the stove burns and what I have read about the NC30 and the 28-4000 burn temps and air intake settings, I'm tempted to believe the door-open readings more than the door closed readings.

If i use the pipe damper to set it at -.05 with the door closed (this is a fully closed pipe damper setting with sub 30*F outside temps... I get a verrry slow burn, with some smoke smell coming into the house as the fire burns down (about 2.5-3 hours in).

Is this normal for my Dwyer Mark II... why would I get these larger draft numbers with the door closed?
 
More vacuum with the door closed is normal. with it open the chimney has a unlimited amount of air, with it closed the chimney has to “pull/vacuum” the air from the stove.
 
Hi Guys - so i've been running a englander 28-4000 for a couple of years and have a pretty good handle on how everything is running, and I'm getting it to produce great heat with around a 6 hour burn. I have been getting quite a bit of black crystal creosote, I would say 3-4 cups 2x per year on cleanings.

Setup as you go up the chimney: Stove- Manometer inserted (6" above stove) - Manual Pipe damper - Condar Probe thermometer - 90* elbow, 4ft horizontal through the masonry wall to T and then 28' insulated stainless liner through outside masonry chimney.

Manometer is a dwyer mark II, connected by 1/4" copper tubing (no connectors, just a hole drilled in the pipe and tube snugly fit.

Here's the goofy thing: My draft readings are running in the -.10 to -.15 range when the door is closed and no pipe damper being used (when stove is at operating temp... and if I open the door at that stage, I get a -.05 to -.07 reading. SO it seems that by closing the door it causes my draft readings to increase by about 2x.

Which one do I use? Based on how the stove burns and what I have read about the NC30 and the 28-4000 burn temps and air intake settings, I'm tempted to believe the door-open readings more than the door closed readings.

If i use the pipe damper to set it at -.05 with the door closed (this is a fully closed pipe damper setting with sub 30*F outside temps... I get a verrry slow burn, with some smoke smell coming into the house as the fire burns down (about 2.5-3 hours in).

Is this normal for my Dwyer Mark II... why would I get these larger draft numbers with the door closed?
The door open readings mean nothing. Go by door closed
 
^^Yep^^