On Wednesday, June 21, 2017 at 8:43:22 AM UTC-4, Leon wrote:
DerbyDad03 wrote:
On Tuesday, June 20, 2017 at 7:24:40 PM UTC-4, Leon wrote:
On 6/20/2017 11:58 AM, DerbyDad03 wrote:
On Tuesday, June 20, 2017 at 12:11:07 PM UTC-4, Leon wrote:
On 6/20/2017 10:35 AM, DerbyDad03 wrote:
On Tuesday, June 20, 2017 at 9:55:48 AM UTC-4, Leon wrote:
On 6/19/2017 9:23 PM, DerbyDad03 wrote:
I've often heard that using a bathroom exhaust fan to exhaust finishing odors
is bad idea, but I'm sure there are certain conditions that would have to be
present for it to really be a danger.
Consider this room:
9' x 12' x 7'
South West corner: A door that opens to the main part of the basement
North West corner: A door that opens to the great outdoors (screened)
Consider this idea:
Mount a 140 CFM bathroom exhaust fan in the North East corner (opposite
the 2 doors). If my calculations are right, that's about 40% more than
the minimum CFM for a bathroom of that size.
https://www.amazon.com/gp/product/B01E0KV5J0
Planned uses: Occasionally exhaust odors from primer, paint, mineral spirits,
oil based stains, oil based poly, farting, etc. No spraying. Brush or wipe-on
only. Small projects or small parts of large projects. e.g. stain a headboard,
paint a dresser, etc. Not to be used when the air is dusty, although
adding a holder for a furnace filter is a possibility.
What would it take for this to go boom?
FWIW, the fan shown below, placed on a stool by the door to the great
outdoors hasn't blown the place up yet. Of course, it's only been about 35
years, so there's still time.
http://i.imgur.com/QzieJU1.jpg
That thing is a beast. I don't know the CFM rating, but it'll dry a pair
of jeans in about an hour.
I am no expert on this but IMHO any "not rated for explosive fumes" fan
can cause an explosion if the air to fuel mixture is right.
One step to insuring that the air fuel mixture is not right is to have
the fan on BEFORE you mix the fuel into the air. Read that as keeping
the fumes dispersed before they have time to accumulate. IF the fuel
concentration is to low to begin with there is less chance of the fan or
it's switch creating the spark in the explosive environment.
Personally I would not draw fresh air in to exhaust out through a small
fan. If the fan does not exhaust directly out side, or if the duct has
a leak in the attic, you might be causing a dangerous situation in your
attic, or where ever the duct work runs.
I would pressurize the room to vent fumes out the large doors. Run the
exhaust fan backwards. Or put a fan on the south door blowing in and a
fan on the north door blowing out. AND another fan in the room to keep
the air moving.
The fan will exhaust to the exterior via a 4" rigid duct, through the rim joist,
just like a dryer vent would. The fan will be less than 4' from the exterior
vent with no turns that will obstruct air flow.
And that scenario would scare me to death, you have a carburetor
concentrating the fumes into a small exit hole and those exhaust ducts
are designed to deliver non combustibles so if they leak no danger. In
this case if they leak into your attic.......
I don't understand your attic concern.
Perhaps I should explain. This room is in the basement and has walk-out
access to the back yard. The 4' duct will run in the exposed ceiling
joist bay. Fan in joist bay, duct in same joist
bay, out through the rim joist and into the back yard. Any leaks will
simply return right back into
the room after passing through the fan. Nothing goes up to the attic.
The duct is all within the
same room right up until it leaves the house.
Any leaks would simply mean that not all of the air is being turned
over. I'm sure the "fan by
the door" method I've been using for 35 years isn't turning over the
air efficiently considering
it is on the same wall as the interior door to the basement. At least
the new fan will be on the
opposite side of the room from the 2 doors, drawing make up air in and across the room.
Am I missing something regarding your "leak into the attic" concern?
No, I was missing where you live. LOL We have no floor joists except
between floors, no basement. I thought the joists you were talking
about would be in the attic or between floors. In other words all enclosed.
Ah! It all makes sense now. ;-)
I take it you've never had the pleasure of drilling a 4" hole for an exhaust
vent in a 2x rim joist above the cinder block foundation wall. It's pure
joy!
A what in a where? LOL. NO, I have not.
The hardest part can be locating the hole so it lands where you want it in the joist space
above the foundation, taking into consideration the siding and other factors on the exterior.
One trick that I have used is to chuck a piece of a wire hanger into a drill, locate where I
want the center of the 4" hole to be on the inside and use the wire to drill a small hole through
rim joist, siding, etc.
Then I go outside, find the end of the wire and adjust the "center" if required/possible. Now I
can drill the big hole from the outside where I typically have more room as opposed to trying to drill the hole up in the joist space.
That's the plan for tonight.