back draft.negative air flow

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boots5050

Member
Hearth Supporter
Sep 26, 2008
19
connecticut
Here is my situation
I have an older model Jotul 118b, it is located in my basement ( house dimensions approx. 30 x 30 )
In my basement I also have a pellet stove, which burns 24 hours a day as well as a dryer, furnace which rarely runs and a gas water heater.
I have the stove 45 degree out through my basement wall and up almost 28 feet
I noticed lately that when the stove is not running cool air seems to be coming into the room from the outside pipe, I am having a lot of back drafting and smoke come back into the room
Could this be because of the pellet stove is sucking too much air out of the basement
I try and light the fire but more often than not I have to shut it down due to expelled smoke
Any ideas on this would be helpful
 
Have you cleaned the flue and cap recently?
 
Sounds like a negative pressure issue. There are lots of competing appliances going for the air in the basement. Can the pellet stove be connected to an outside air kit?
 
Sounds like you've got quite a bit going on there. Dryer, furnace, water heater, wood stove, pellet stove all trying to expel air out of the basement (a 900 square foot space?). Not to mention the natural draft of hot air from the stoves wanting to rise out of the basement which is also trying to create a negative pressure.

First a word of warning - if you're smelling smoke backing up from the stove (though you say 'when *not* running - so is this smoke from somewhere else...pellet stove, another wood burning appliance, neighbors, etc?) - then you know you have back draft issues on that flue. It's highly likely you have back draft issues on the gas appliances, too. Though they would tend to be more odorless, they still have the potential for CARBON MONOXIDE - so be careful and use a detector!

As for solutions, seems like you need to get fresh air down there somehow. You could try a vent or open window, though that's generally not very desirable in winter. Outdoor air kits for some appliances may help though would be somewhat expensive. You could try to isolate the basement by closing (or installing) a door at the bottom of the stairs...that would at least help stop some of the natural hot air draft...though that may be desirable for heating the rest of the house. Some people report success using a fan in the stair well to help 'stuff' cold air into the basement from the rest of the house. That might be the quickest/easiest thing to try. In extreme cases I think we even had one guy put a fan 'in' the door to the basement and a small vent at the top...idea being to positively pressurize the basement, but allow some hot air back out.

Either way - again, BE CAREFUL if you have the gas appliances and everything else fighting for draft, the 'everything else' might win and leave you with a basement full of odorless carbon monoxide.
 
if air change is an issue you could get a fan in a can and run it off a timer or wire it so it cycles with the appliance that uses the most btu. or an hrv or erv connected to the existing ductwork. is the furnace a communicating system? that would be even better.
 
Thank you for all the responses
When the stove is cold, I can feel cold air being drawn in from the flue
Once I get the fire started it drafts ok, I have a homemade duct coming from the outside that I attach to the front of my older
black bear
Cory, am I supposed to try that fan at the top of the stairs, facing towards the basement to draw fresher air down there?
my furnace as well as my water heater are direct vented to the chimney, my dryer vented to the outside
Again, this is only on start up, I feel the cold air pushing in from my outside vent
thanks again
 
One thing I forgot to mention about the older Jotul 118 is that it has a baffle plate, this is a " cigar burner"
The baffle extends towards the front of the stove, upon starting the fire, the smoke hits the baffle up top and then is drawn into the room,
I am experimenting with an intake, I will keep everybody informed
 
if air change is an issue you could get a fan in a can and run it off a timer or wire it so it cycles with the appliance that uses the most btu. or an hrv or erv connected to the existing ductwork. is the furnace a communicating system? that would be even better.
My pellet stove has the most btu, furnance, water heater, dryer run infreguently
Only happens on start up. I feel cool air being drawn into the room when I open the stove door
This older Jotul had a baffle top plate which draws the heat towards the front of the stove and is then expelled
 
My pellet stove has the most btu, furnance, water heater, dryer run infreguently
Only happens on start up. I feel cool air being drawn into the room when I open the stove door
This older Jotul had a baffle top plate which draws the heat towards the front of the stove and is then expelled
sounds like a fan in a can would work well. you can wire it to come on before the stove does. the only issue is it not heated air. at least I have never seen one with heat. you would think they would make it. do you have this problem even when the stove is the only appliance running?
 
Thank you for all the responses
When the stove is cold, I can feel cold air being drawn in from the flue
Once I get the fire started it drafts ok, I have a homemade duct coming from the outside that I attach to the front of my older
black bear
Cory, am I supposed to try that fan at the top of the stairs, facing towards the basement to draw fresher air down there?
my furnace as well as my water heater are direct vented to the chimney, my dryer vented to the outside
Again, this is only on start up, I feel the cold air pushing in from my outside vent
thanks again

Are the furnace, hw heater and pellet stove all on separate flues from the wood stove?
 
Are the furnace, hw heater and pellet stove all on separate flues from the wood stove?
yes, each one has a separate flue, the water heater and furnace are vented to the chimney
My house is over 100 years old, I sealed the walls, put insulation in the sill plate, I think I may have over sealed the basement, very little outside air is able to come in
 
sounds like a fan in a can would work well. you can wire it to come on before the stove does. the only issue is it not heated air. at least I have never seen one with heat. you would think they would make it. do you have this problem even when the stove is the only appliance running?
a fan? where would I locate it, I was thinking about trying a Condar supply ventilator for some fresh air, relieving the negative pressure in the basement
 
[quo


te="Corey, post: 1602824, member: 50"]Sounds like you've got quite a bit going on there. Dryer, furnace, water heater, wood stove, pellet stove all trying to expel air out of the basement (a 900 square foot space?). Not to mention the natural draft of hot air from the stoves wanting to rise out of the basement which is also trying to create a negative pressure.

First a word of warning - if you're smelling smoke backing up from the stove (though you say 'when *not* running - so is this smoke from somewhere else...pellet stove, another wood burning appliance, neighbors, etc?) - then you know you have back draft issues on that flue. It's highly likely you have back draft issues on the gas appliances, too. Though they would tend to be more odorless, they still have the potential for CARBON MONOXIDE - so be careful and use a detector!

As for solutions, seems like you need to get fresh air down there somehow. You could try a vent or open window, though that's generally not very desirable in winter. Outdoor air kits for some appliances may help though would be somewhat expensive. You could try to isolate the basement by closing (or installing) a door at the bottom of the stairs...that would at least help stop some of the natural hot air draft...though that may be desirable for heating the rest of the house. Some people report success using a fan in the stair well to help 'stuff' cold air into the basement from the rest of the house. That might be the quickest/easiest thing to try. In extreme cases I think we even had one guy put a fan 'in' the door to the basement and a small vent at the top...idea being to positively pressurize the basement, but allow some hot air back out.

Either way - again, BE CAREFUL if you have the gas appliances and everything else fighting for draft, the 'everything else' might win and leave you with a basement full of odorless carbon monoxide.[/quote]

I need some fresh air down there, my house is old, but the basement I think has been over sealed, new windows, wall sealed with primer water sealer, insulated sill plates etc
A fan at the top of the stairs pointing down? do you think that may be effective, or do I want to draw the heat upstairs?
I have two small floor vents to help the heat rise to the top floors, I tried small fans in these vents to draw upwards but it created more negative pressure in the basement
My struggle is providing enough fresh air to run everything together in the basement
 
[quo


te="Corey, post: 1602824, member: 50"]Sounds like you've got quite a bit going on there. Dryer, furnace, water heater, wood stove, pellet stove all trying to expel air out of the basement (a 900 square foot space?). Not to mention the natural draft of hot air from the stoves wanting to rise out of the basement which is also trying to create a negative pressure.

First a word of warning - if you're smelling smoke backing up from the stove (though you say 'when *not* running - so is this smoke from somewhere else...pellet stove, another wood burning appliance, neighbors, etc?) - then you know you have back draft issues on that flue. It's highly likely you have back draft issues on the gas appliances, too. Though they would tend to be more odorless, they still have the potential for CARBON MONOXIDE - so be careful and use a detector!

As for solutions, seems like you need to get fresh air down there somehow. You could try a vent or open window, though that's generally not very desirable in winter. Outdoor air kits for some appliances may help though would be somewhat expensive. You could try to isolate the basement by closing (or installing) a door at the bottom of the stairs...that would at least help stop some of the natural hot air draft...though that may be desirable for heating the rest of the house. Some people report success using a fan in the stair well to help 'stuff' cold air into the basement from the rest of the house. That might be the quickest/easiest thing to try. In extreme cases I think we even had one guy put a fan 'in' the door to the basement and a small vent at the top...idea being to positively pressurize the basement, but allow some hot air back out.

Either way - again, BE CAREFUL if you have the gas appliances and everything else fighting for draft, the 'everything else' might win and leave you with a basement full of odorless carbon monoxide.

I need some fresh air down there, my house is old, but the basement I think has been over sealed, new windows, wall sealed with primer water sealer, insulated sill plates etc
A fan at the top of the stairs pointing down? do you think that may be effective, or do I want to draw the heat upstairs?
I have two small floor vents to help the heat rise to the top floors, I tried small fans in these vents to draw upwards but it created more negative pressure in the basement
My struggle is providing enough fresh air to run everything together in the basement[/quote]

I do have a Carbon Monoxide detector
 
a fan? where would I locate it, I was thinking about trying a Condar supply ventilator for some fresh air, relieving the negative pressure in the basement
a fan in a can is an approved method of bringing fresh air into the house. you can put it near the appliance and wire it for a couple different scenarios. I will search for a link. I use these if an hrv or erv is not an option.
 
Here is my situation
I have an older model Jotul 118b, it is located in my basement ( house dimensions approx. 30 x 30 )
In my basement I also have a pellet stove, which burns 24 hours a day as well as a dryer, furnace which rarely runs and a gas water heater.
I have the stove 45 degree out through my basement wall and up almost 28 feet
I noticed lately that when the stove is not running cool air seems to be coming into the room from the outside pipe, I am having a lot of back drafting and smoke come back into the room
Could this be because of the pellet stove is sucking too much air out of the basement
I try and light the fire but more often than not I have to shut it down due to expelled smoke
Any ideas on this would be helpful
Good advice about cleaning pipe and flue though it wouldn't prevent negative draft.Opening a window or door upon start up will reverse the draft until the pipe gets hot then the window or door can be closed.I had a undersized soapstone in my cellar that didn't hold the heat long enough after the fire went out so the downdraft was there in the morning.I put in a larger soapstone and it provided enough heat in the morning that I still had a good up draft and just refilled the stove.So a stove that is large enough to provide heat into the morning will allow you to refill the stove without the down draft issue.Just have to keep the stove running more constantly.
 
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