Whole house fan and reversed draft

Whole house fan and reversed draft

PostBy: lsayre On: Tue May 13, 2014 3:05 pm

My wife cranked up the whole house fan yesterday without opening windows and fortunately at the time I was near the boiler room and in the basement, as I immediately noticed a sulfur odor, and when I checked I saw that the chimneys draft had reversed. By the time my wife had turned the fan off the digital CO meter in the boiler room was already reading 13. Chimney draft immediately returned to normal when she shut the whole house fan off. We opened all of the windows and doors at that point, and the CO detectors upstairs never rose above zero.

Lesson learned that if the whole house fan is running plenty of windows and screen doors need to be open on all levels so it doesn't reverse the draft of the chimney. In fact, I'm questioning if even then it will be wise to run the whole house fan.
lsayre
 
Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Anthracite Pea
Other Heating: Resistance Boiler (It has been fixed!)

Re: Whole house fan and reversed draft

PostBy: northernmainecoal On: Tue May 13, 2014 3:12 pm

Glad you were right there and everyone is safe!
What exactly is a whole house fan?
northernmainecoal
 
Stoker Coal Boiler: EFM 520
Hand Fed Coal Stove: Hitzer 30-95
Coal Size/Type: Rice/Nut

Re: Whole house fan and reversed draft

PostBy: lsayre On: Tue May 13, 2014 3:25 pm

northernmainecoal wrote:Glad you were right there and everyone is safe!
What exactly is a whole house fan?


It's a louvered fan which exhausts into the attic and cools the whole house down. It's a substantial fan. The windows and screen doors were mostly closed because it was raining cats and dogs outside.

The reason why I was in the basement is that for 2 hours straight the tornado sirens were going off on our street (we live right across from the Township Hall) and also in the communities to both the north and south of us. When the warning was lifted my wife (who was also in the basement for 2 hours) immediately said "I'm going upstairs to turn the whole house fan on to cool it down in here", and I stayed behind in the basement as she went up and turned it on.
Last edited by lsayre on Tue May 13, 2014 3:55 pm, edited 2 times in total.
lsayre
 
Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Anthracite Pea
Other Heating: Resistance Boiler (It has been fixed!)


Re: Whole house fan and reversed draft

PostBy: lsayre On: Tue May 13, 2014 3:32 pm

The manometer indicated draft was -0.03" to -0.04" and it reversed to +0.01" when the whole house fan was turned on.
lsayre
 
Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Anthracite Pea
Other Heating: Resistance Boiler (It has been fixed!)

Re: Whole house fan and reversed draft

PostBy: rberq On: Tue May 13, 2014 3:58 pm

I used to worry about running the clothes dryer for the same reason, though obviously it is a much smaller fan, so I would open the laundry room window. But apparently my house is so leaky that the draft was going OUT the window rather than in. No sick house syndrome here, just lots of fresh air. :o
rberq
 
Hand Fed Coal Stove: DS Machine 1300
Coal Size/Type: Nut -- Kimmel/Blaschak/Reading
Other Heating: Oil hot water radiators, propane

Re: Whole house fan and reversed draft

PostBy: Rob R. On: Tue May 13, 2014 4:26 pm

Larry, do you have a vent in the boiler room for make up air?

Also, do you have a cover made for that whole house fan so it doesn't "ventilate" your house in the winter?
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Other Heating: Dad's 1953 EFM Highboy

Re: Whole house fan and reversed draft

PostBy: Sting On: Tue May 13, 2014 4:34 pm

Rob R. wrote:Larry, do you have a vent in the boiler room for make up air?


Any vent of logical size to feed combustion air to an appliance would be vastly overwhelmed by a Whole House fan. Even a combination of [comparatively small] bath and stove fans can offset appliance draft. Many open windows is the only solution.
Sting
 
Other Heating: BurnHAM=NG-gas

Re: Whole house fan and reversed draft

PostBy: McGiever On: Tue May 13, 2014 5:23 pm

It isn't pretty when a whole house fan is turned on in the winter with a open fireplace burning.
McGiever
 
Stoker Coal Boiler: AXEMAN-ANDERSON 130 "1959"
Hot Air Coal Stoker Stove: HARMAN MAGNUM
Hand Fed Coal Stove: RADIANT HOME AIR BLAST
Baseburners & Antiques: OUR GLENWOOD 111 BASEBURNER "1908"
Coal Size/Type: PEA / ANTHRACITE, NUT-STOVE / ANTHRACITE
Other Heating: Ground Source Heat Pump
Stove/Furnace Make: Hydro Heat /Mega Tek

Re: Whole house fan and reversed draft

PostBy: lsayre On: Tue May 13, 2014 5:44 pm

Rob R. wrote:Larry, do you have a vent in the boiler room for make up air?

Also, do you have a cover made for that whole house fan so it doesn't "ventilate" your house in the winter?


I still need to get outside air into the boiler room. Right now it is wide open to the basement, but I would like to close it off from the basement.

The whole house fan has louvers that close when it isn't running. Perhaps I should cover the louvers up with plastic sheeting during the winter.
Last edited by lsayre on Tue May 13, 2014 8:23 pm, edited 1 time in total.
lsayre
 
Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Anthracite Pea
Other Heating: Resistance Boiler (It has been fixed!)

Re: Whole house fan and reversed draft

PostBy: Rob R. On: Tue May 13, 2014 6:02 pm

Sting wrote:
Rob R. wrote:Larry, do you have a vent in the boiler room for make up air?


Any vent of logical size to feed combustion air to an appliance would be vastly overwhelmed by a Whole House fan. Even a combination of [comparatively small] bath and stove fans can offset appliance draft. Many open windows is the only solution.


Yep...but this still seemed like a good time to mention make up air.
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Other Heating: Dad's 1953 EFM Highboy

Re: Whole house fan and reversed draft

PostBy: Rick 386 On: Tue May 13, 2014 7:22 pm

lsayre wrote:
I still need to get outside air into the boiler room. Right now it is wide open to the basement, but I would like to close it off from the basement...................................



Larry,

Can you seal off the basement door from the first floor ?? That way you can provide make up air in the basement for the boiler only. Sealing the door would prevent the draw extending into the basement. Or at least severely limit it.

Our old twin farmhouse has 2 doors open to the basement from inside each side of the upstairs and also 2 bilco doors on either end of the basement. They do not seal real tight either. We do run a large about 18" diameter fan in the 2nd floor window at the top of the stairs. We rarely see a backflow on the flue.

I have mentioned on here several times before that at my old shop whenever I would turn on the spraybooth fan, it would backdraft both the coal and oil burner flues. Only solution was to fully open the far shop window. And I was using a 24" fan attached to a 1/2 hp motor. Yeah it did draw some air !!!!!




Rick
Rick 386
 
Stoker Coal Boiler: AA 260 heating both sides of twin farmhouse
Hot Air Coal Stoker Stove: LL Hyfire II w/ coaltrol in garage
Coal Size/Type: Pea in AA 260, Rice in LL Hyfire II
Other Heating: Gas fired infared at work

Re: Whole house fan and reversed draft

PostBy: coalkirk On: Tue May 13, 2014 8:07 pm

lsayre wrote:In fact, I'm questioning if even then it will be wise to run the whole house fan.


I think you answered your own question. Whole house fans and combustion appliances don't play nice together.
coalkirk
 
Stoker Coal Boiler: Harman VF3000
Coal Size/Type: antrhcite/rice coal

Re: Whole house fan and reversed draft

PostBy: rubicondave33 On: Tue May 13, 2014 8:16 pm

We ran a whole house fan for years (before I installed central air) with no issues. I have make up air for my boiler, and the boiler room has a door on it as well. The space where my whole house fan lived is now the return air for my air handling unit in the attic.
rubicondave33
 
Stoker Coal Boiler: EFM DF520
Coal Size/Type: Rice/Anthracite
Stove/Furnace Make: efm
Stove/Furnace Model: DF520

Re: Whole house fan and reversed draft

PostBy: lsayre On: Tue May 13, 2014 8:22 pm

Rick 386 wrote:
Larry,

Can you seal off the basement door from the first floor ?? That way you can provide make up air in the basement for the boiler only. Sealing the door would prevent the draw extending into the basement. Or at least severely limit it.

Rick


I can shut the door at the top of the stairs coming up from the basement. With a window open in the basement, and windows open upstairs, and the door closed between the basement and the upstairs, it should bode better for the whole house fan.
lsayre
 
Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Anthracite Pea
Other Heating: Resistance Boiler (It has been fixed!)

Re: Whole house fan and reversed draft

PostBy: Sting On: Wed May 14, 2014 7:41 am

Rob R. wrote:Yep...but this still seemed like a good time to mention make up air.


and an excellent opportune moment , it was sir Image
Sting
 
Other Heating: BurnHAM=NG-gas