Wood stoves, high humidity regions and HVAC

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.

EbS-P

Minister of Fire
Jan 19, 2019
3,548
SE North Carolina
This topic probably doesn’t apply to most of you but I think it’s something that in need to address. Our summers are hot and humid. RH here in SE NC is higher than New Orleans or Miami in august and September and December. All three months we average 70% RH or higher.

I’m planning a complete HVAC replacement in the future, hopefully when the supply chain is no longer restricted) which will include major air sealing and additional insulation in the attic (which I will be doing now). All of this will start with a blower door test.

Questions I I’ve been pondering.
1. Should I be plugging the liners in the summer ?

2. Blower door tests and wood stoves. Do you plug the flue or not? Test it both ways? Who ever comes out to do mine will probably never have done one on a home with an EPA stove.

3. Has anyone done a diy blower door/window test. I have a thermal camera. Seem like for the rental cost of a fan and some cardboard and tape a could wait for a cold day and put the house under negative pressure and find most of the leak relatively easily. Thoughts?

4. How tight is to tight without makeup air? Does anyone have an AHC number where you needed makeup air? It’s there a rule of thumb?

(I don’t think I have a chance of getting this house anywhere close to tight enough to worry about but if there are numbers out there I’m all ears. My guesstimate 50 cfm per stove (3000 cu ft per hour) for 8000 cu ft house (1000 sq ft at 8’ ceilings) works out to be .375 of the house volume per hour which seems small but I don’t recall what pressure the blower door tests are run at, and we know tight homes need makeup air).

I appreciate any feedback.

Evan
 

stoveliker

Minister of Fire
Nov 17, 2019
6,267
Long Island NY
I have never done a blower test.
I do take my stove.pipe off when the burning season ends and I clean the flue. I then plug both the stove and the flue at the thimble. (I have a 2 ft rise and ann18" horizontal run between stove and thimble).

So no humidity comes in the hole thru the flue, and my stove is closed. I also plug the air inlet of the stove. Finally, i put a pot of damprid in the stove.

At the end of the season I have 3/4" of water in there.

Not doing this I do see rust developing in summer inside the stove.


I live near the water on Long Island. Not as humid as you (or East TN). But humid enough that my minisplit keeps it's section of susans nice and green during the drought we have here.