Oops! Enough air sealing.

[Squirrel]

Wife and I arrived home to a cool house yesterday evening. I went to light the stove and she went in the laundry room. I had just got the stove alight but not even warm when she started the dryer.
I now know that our dryer can empty a chimney full of smoke into the kitchen in 2.1 seconds, that all our smoke alarms work, that the air sealing I did on the house worked and to remind the wife to open the laundry room window a crack when running the dryer.

 

[iamlucky13]

Do you have a makeup air vent? We were told it is required by code when we had our stove installed.

So far, we've had no problems with ours backdrafting, even with the dryer, and I'm sure at least one bathroom fan running simultaneously. Then again, I've still got more sealing to do, and our chimney drafts pretty strongly.

 

[Highbeam]

Do you have a makeup air vent? We were told it is required by code when we had our stove installed.

Yes, required for my stoves too. Plus they are just a great idea.

Imagine now if Squirrel's house had been equipped with a regular natural vent gas water heater. Wife runs dryer and unknowingly sucks all of the water heater exhaust and carbon monoxide into the home while you sleep.

 

[bholler]

Imagine now if Squirrel's house had been equipped with a regular natural vent gas water heater. Wife runs dryer and unknowingly sucks all of the water heater exhaust and carbon monoxide into the home while you sleep.

That is why spill switches should be on every gas appliance. We come across problems like this pretty often with new construction it usually shows up with fireplaces but regular wood stoves can be a problem to. You do have to be careful with the placement of you fresh air intake though if you put it in the wrong spot it can cause other problems

 

[Highbeam]

That is why spill switches should be on every gas appliance.

Never seen one. Are they a code requirement? Big range hoods can cause this phenomenon too. It's not really a stove issue as much as an air sealing issue.

 

[Squirrel]

No make up air vent, in fact they are not recommended in Canada. At -40 they would cause problems. New houses all have heat recovery ventilation systems but mine is not new. It was just a case of bad timing mixed with atmospheric conditions.
We are also legislated to have working smoke and CO detectors, even without a "burning" appliance.

 

[bholler]

Never seen one. Are they a code requirement? Big range hoods can cause this phenomenon too. It's not really a stove issue as much as an air sealing issue.

They are the little sensor clipped on to the draft hoods on water heaters and furnaces. They are code in some areas and not others. They sense fumes spilling out of the draft hood and shut down the unit

 

[iamlucky13]

No make up air vent, in fact they are not recommended in Canada. At -40 they would cause problems. New houses all have heat recovery ventilation systems but mine is not new.

Wouldn't an HRV perform effectively the same function just without wasting as much heat?

 

[Squirrel]

Wouldn't an HRV perform effectively the same function just without wasting as much heat?

It sure would, but for now I'll throw on more wood and open a window. That even works during power outages.

 

[begreen]

It sure would, but for now I'll throw on more wood and open a window. That even works during power outages.

How does having a window open work better at -40F than having an OAK tied to the stove? (Well other than it's cheaper and easier )

 

[Squirrel]

How does having a window open work better at -40F than having an OAK tied to the stove? (Well other than it's cheaper and easier )

I don't know, I don't do either one. My draft is usually fantastic. I have a smoke alarm on a low ceiling two feet over from the stove (The alarm was there first) and last night was the first time it went off (without me cooking) in years.

 

[begreen]

Well at least the air sealing works.

 

[begreen]

Thinking more about this. With a tighter house you will want to watch for issues. Draft will decrease as the fire dies down. You don't want it to reverse when asleep and something comes on that competes for combustion air. Examples would be a furnace or boiler, gas or oil hot water heater. An HRV might be the best solution for peace of mind and fresh air exchange.

 

[Squirrel]

No gas or oil in the house and several CO detectors. In the past I had to call an ambulance for a co-worker with CO poisoning from an over-heated bearing so I know you can't be too careful.

 

[Wisneaky]

They are the little sensor clipped on to the draft hoods on water heaters and furnaces. They are code in some areas and not others. They sense fumes spilling out of the draft hood and shut down the unit

My gas water heater is a power vent. Is it recommended to use it on these also?

 

[bholler]

My gas water heater is a power vent. Is it recommended to use it on these also?

Nope the power venter should have its own sensors

 

[DTrain]

I live in a not very tight cape and we have a 600 cfm range hood. I cant have it running on a cold start or I'll get smoke in the house. If the stove is running already I can run it on low and be fine.

 

[Highbeam]

My gas water heater is a power vent. Is it recommended to use it on these also?

I grew up around gas water heaters with zero electronics. These could and would backdraft if conditions allowed.

 

[Highbeam]

No make up air vent, in fact they are not recommended in Canada. At -40 they would cause problems.

I don't believe this to be true. Likely a myth like not burning pine. We often have OAK debates and coldness is usually the reason that you should install the OAK.

Even at -40 the only problems would be icing or condensation on the actual OAK duct to the stove which would be mitigated by insulation. The alternative is of course -40 degree air being sucked into the home through that open window or cracks in the envelope. That cold air will replace heated room air being sucked out by the stove. That cold air is extremely dry so your indoor humidity will fall as well as the obvious need to heat it.

 

[Highbeam]

The Ontario Building Code (OBC)

9.22.1.4. Combustion Air

(1) Every solid fuel-fired fireplace, including a factory-built fireplace, shall have a supply of combustion air from outdoors in accordance with Sentences (2) to (7).

(2) The combustion air shall be supplied by a noncombustible and corrosion-resistant supply duct.

(3) The supply duct shall have,

(a) a diameter of not less than 100 mm or equivalent area, and

(b) an exterior intake for entry of air from the outdoors.

 

[Jo191145]

Yep, if I lived anywhere that got -40 degrees I would definately tighten up my house.
I would also install an OAK. It makes perfect sense. That stove is sucking in cold air somewhere. Better to have it contained as opposed to flowing across the room.
-3.5 was the coldest it got last year. Just installed my first OAK on my new PH. It can only help. Works great so far.

 

[Squirrel]

The Ontario Building Code (OBC)

9.22.1.4. Combustion Air

(1) Every solid fuel-fired fireplace, including a factory-built fireplace, shall have a supply of combustion air from outdoors in accordance with Sentences (2) to (7).

(2) The combustion air shall be supplied by a noncombustible and corrosion-resistant supply duct.

(3) The supply duct shall have,

(a) a diameter of not less than 100 mm or equivalent area, and

(b) an exterior intake for entry of air from the outdoors.

That was in 1990, in 1995 it was changed to "Where the only spillage-susceptible equipment present is woodburning, there is an exception requiring only the installation of a carbon monoxide detector to provide warning of spillage should it occur."
Canada has done lots of research on this, you can read the details here. http://www.woodheat.org/outdoor-combustion-air-in-the-canadian-national-building-code.html

 

[Capt_Ron]

I live in a not very tight cape and we have a 600 cfm range hood. I cant have it running on a cold start or I'll get smoke in the house. If the stove is running already I can run it on low and be fine.

Same thing here. Before we had the wood stove, it was just a fireplace. 1050cfm Thermador range hood. I have windows very close to crack open for air draw. One night I had a nice fire going, started up the range hood and forgot to crack open the window. Within a few minutes, the whole lower level of the house was full of smoke from the draft reversing in the fireplace.

 

[Highbeam]

That was in 1990, in 1995 it was changed to "Where the only spillage-susceptible equipment present is woodburning, there is an exception requiring only the installation of a carbon monoxide detector to provide warning of spillage should it occur."
Canada has done lots of research on this, you can read the details here. http://www.woodheat.org/outdoor-combustion-air-in-the-canadian-national-building-code.html

While I believe you that the code may have changed, I will not visit that site. It is known to be a misleading and generally untrustworthy resource.

 

[Squirrel]

While I believe you that the code may have changed, I will not visit that site. It is known to be a misleading and generally untrustworthy resource.

Ah, so that's why some of it's main supporters are Selkirk, Obadiah's, Morso, Hearth Products Association of Canada etc. etc. All untrustworthy folk.