Englander 28-3500 End of burn CO

[Scotth]

Hi All,
I moved into a new home with an existing 28-3500 that is installed in a 12x20 basement (a basement under an addition that is not connected to the main basement)
Blower is connected and ductwork runs to 3 vents upstairs and one vent to basement.
Chimney is 24’ Selkirk that runs up the north facing side of the house.
Flue design is 6” stove pipe rising about 1’ to a 45, to a 2’ straight, to another 45 into the chimney. No damper.

On my first couple burns, I noticed that when the stove got hot enough and the fan kicked on, my coals started to fade.
I figured that with the room being so small, the stove was starving for air, so I used a hole saw to cut a hole in my door leading outside and installed a 4” dryer vent with hose and directed the hose toward the stove. Problem solved.
I generally run the door vent about a turn and 1/2 open and the top vent 3/4 closed when I’m ready to call it a night.
I go to bed about 11:00, thinking that all is good until our family gets awoken at 2:30 by the CO detector.
At this point, we vent the house & I go to remedy the situation. What I generally find is a cold flue pipe and small chunks of wood smoldering in the fire box, with no smoke in the room.

I really enjoy having a fire to give me something to do while saving oil, but don’t feel comfortable putting my family at risk of CO poisoning. My wood is mostly maple, cut in Sept ‘19, split in May ‘20 and stacked in August. The wood burns quickly with no sizzle, but I haven’t checked moisture content. I haven’t measured draft, as I understand that taller chimneys generate more draft & I get a good draw up the flue after holding a lit newspaper at the rear of the firebox. I have my baffle pushed all the way to the back of the stove.

Sorry I’m rambling, but I wanted to paint a clear picture of my situation.
In short, I really want to be a wood burner and feel comfortable with my setup.
I was thinking of calling a local chimney guy, but through spending time reading posts here, I feel you guys know more about this Stove.
Looking forward to any suggestions you may have.
Thanks!

 

[bholler]

Hi All,
I moved into a new home with an existing 28-3500 that is installed in a 12x20 basement (a basement under an addition that is not connected to the main basement)
Blower is connected and ductwork runs to 3 vents upstairs and one vent to basement.
Chimney is 24’ Selkirk that runs up the north facing side of the house.
Flue design is 6” stove pipe rising about 1’ to a 45, to a 2’ straight, to another 45 into the chimney. No damper.
On my first couple burns, I noticed that when the stove got hot enough and the fan kicked on, my coals started to fade.
I figured that with the room being so small, the stove was starving for air, so I used a hole saw to cut a hole in my door leading outside and installed a 4” dryer vent with hose and directed the hose toward the stove. Problem solved.
I generally run the door vent about a turn and 1/2 open and the top vent 3/4 closed when I’m ready to call it a night.
I go to bed about 11:00, thinking that all is good until our family gets awoken at 2:30 by the CO detector.
At this point, we vent the house & I go to remedy the situation. What I generally find is a cold flue pipe and small chunks of wood smoldering in the fire box, with no smoke in the room.
I really enjoy having a fire to give me something to do while saving oil, but don’t feel comfortable putting my family at risk of CO poisoning.
My wood is mostly maple, cut in Sept ‘19, split in May ‘20 and stacked in August. The wood burns quickly with no sizzle, but I haven’t checked moisture content.
I haven’t measured draft, as I understand that taller chimneys generate more draft & I get a good draw up the flue after holding a lit newspaper at the rear of the firebox.
I have my baffle pushed all the way to the back of the stove.
Sorry I’m rambling, but I wanted to paint a clear picture of my situation.
In short, I really want to be a wood burner and feel comfortable with my setup.
I was thinking of calling a local chimney guy, but through spending time reading posts here, I feel you guys know more about this Stove.
Looking forward to any suggestions you may have.
Thanks!

Is it hooked to a cold air return vent or is the distribution fan pulling from the room the stove is in?

 

[Scotth]

There is no return vent. Pulling from the room.
when the fan is on, air rushes through the dryer vent and doorknob hole of my door leading outside

 

[trx250r87]

There is no return vent. Pulling from the room.
when the fan is on, air rushes through the dryer vent and doorknob hole of my door leading outside

This sounds far from ideal. It sounds like your furnace room is trying to pull combustion air and blower air from a space that is being fed by a couple small holes leading to the outside. This might work for combustion air but not for the blower fan. You're also pressurizing your house with a ton of air as it has no place to go. I'm guessing your static pressure of your ductwork as well as draft change from the time you start a fire to the time you reach coaling stage.

You really need a return air into this space!

Eric

 

[Scotth]

Thanks guys.
I have the vent closed for the duct leading to the main basement. If I disconnect that duct from the main trunk, and open the vent in the main basement, will that be an adequate air return?

 

[trx250r87]

Thanks guys.
I have the vent closed for the duct leading to the main basement. If I disconnect that duct from the main trunk, and open the vent in the main basement, will that be an adequate air return?

It's difficult to say, especially without measurents. Does the manual for that furnace give you any information on blower cfm, static pressure requirement or duct surface area measurements? I think the surface area of your return air ducts should be slightly higher than supply air.

Eric

 

[brenndatomu]

Thanks guys.
I have the vent closed for the duct leading to the main basement. If I disconnect that duct from the main trunk, and open the vent in the main basement, will that be an adequate air return?

Some pics would help us understand what you are dealing with...but yes, you need to get return air from the areas that you are pumping the warm air into...or at least from a part of the house that is connected to those areas via open doorways/hallways etc. Some people just leave the basement door open for return air too...might need a half door or a louvered door if you have small kids or pets that need to stay upstairs.

Does the manual for that furnace give you any information on blower cfm, static pressure requirement or duct surface area measurements? I think the surface area of your return air ducts should be slightly higher than supply air.

Its a 850 CFM blower and the supply connector is a single 8" round.
Yes, return air ducts should be ~20% larger than the supply. (minimum)

 

[brenndatomu]

I'd really recommend getting an inexpensive manometer to monitor your draft level too (Dwyer Mark II model 25 is a good/cheap one)
and put a key damper on that stove pipe then too...I bet you get pretty high draft going sometimes with that 24' chimney...I know I do with a 27'

 

[lost in the woods]

sorry posting a little late in the game here. . . i have the same stove, and very similar house set-up. . . #1 i just cut a hole in my floor and installed a vent at the opposite end of the house for my retrurn air. . .. seems to be working out ok. #2 the user/owner manual states to NOT put a damper on stove pipe with the 28-3500. . . . im running mine wide open just as they say to do in the manual. . . . it really eats the wood but conversely i have almost no creosote build-up in the chimney pipe (duravent SS doublewall). . . hope this helps

 

[brenndatomu]

#2 the user/owner manual states to NOT put a damper on stove pipe with the 28-3500. . . .

It also says to not run with chimney draft in excess of -0.05" WC...how would one control that if not with a damper?