Wood smoke pollution causing health problems
We have just about finished renovating when we discovered that my wife is now sensitive to some odours, especially wood smoke. She can react to it long before I notice it.
Currently, we have a two stage mid-efficiency furnace with a 5 inch duct bring combustion air into the furnace room.
I can replace it with a high efficiency unit to eliminate the combustion air duct. I can keep all the windows and doors closed so that less smoky air comes in. I can ensure there are dampers on the dryer vent, range hood, and bath fans.
But how do we get fresh air into the house?
An HRV cannot filter smoky air even with a HEPA filter.
I have not yet found a whole house furnace filtering system that can filter wood smoke. A lot of them can filter tobacco smoke but that is not the same as wood smoke. I am trying to stay away from electrostatic filters as they produce ozone You really need to have activated carbon. And there are probably VOCs that need to be removed as well.
I have talked to a lot of people from HVAC companies to ventilation specialists but no one has been able to give me an adequate solution.
Has anyone in the GBA community ever encountered this problem? And devised a solution? I am really at my wits end trying to find a solution for her. It is difficult to watch someone you love suffer and not able to do anything about it. In the end, we may just have to sell and move but you can never guarantee that the next place will be better.
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Replies
Aaron,
Where is the wood snake coming from? Is there any way to mitigate it at its source?
I learned here that an activated carbon filter works best with low humidity. Thus, in an HRV system, if it is placed on the incoming air after the HRV, the cold outside air will have been warmed first, at which point it will have low humidity (if it is cold outside--and the problem smoke presumably occurs when it's cold outside!). Zehnder has that option available--a filter housing and carbon filter to mount at that point in ductwork coming out of their system. Zehnder is expensive, and there's no reason another HRV couldn't be configured that way, but if you need help configuring that I know they are able to do it.
You can also get interior "air cleaners" with charcoal filters, which can help, keeping at least one room's air clean while you get the HRV installed, but obviously addressing it when it's coming into the house is best.
" I can ensure there are dampers on the dryer vent, range hood, and bath fans."
Note that whenever you run those, you are drawing air into the house through leaks. If you want to eliminate that, you can use the HRV exhaust in the bathrooms and kitchen, together with a recirculating filtering range hood without exhaust (assuming you have electric or induction, not gas, for cooking), and a heat-pump ventless dryer.
Malcolm, there are three homes in the neighbourhood that regularly use their old masonry fireplaces.
One of them is willing to ' burn less'.
Charlie, thanks for the info on the Zehnder HRVs. I will check them out. We purchased an Austin Air purifier with 6.5 Ibs of carbon but a found it of limited effectiveness. We are going to get an IQair Multigas unit instead.
Aaron,
That's a tough situation to be in. Good luck. Hope you can find a satisfactory solution.