Whole house fan install tip?
- Thread starter Fuddy1952
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jaxs
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Ok Fuddy,I'll try and help you with your fan blade question and let the other hands help you decide between whole house fan or a 10 ton refrigerated air unit for your barn? :laughing: Ever picture look's like blade is in different positions but your sketch #1 and pic where air flow direction is marked with Sharpie are correct,,,if,,,rotation is cw looking at end of shaft. I bring up rotation because (A) you say it look's like blade has been moved up and down shaft. That make's me think someone was trying to find the sweet spot while blade was mounted backwards.(B) the fan might have been free because it didn't move enough air due to improper blade orientation. I've replaced hundreds of ac condenser motors where that square nut on your hub was between blades and motor. Ditto for allen setscrews. If I had $50 for every blade a "PRO" installed backwards,I could afford a big hat and new truck. You need long tee-handle allen wrench or square nut socket with ratchet and extension in order to get in there. While you check that out,I'll jump into the debate over correct location of whole house fan.
Few if any direct drive fans can do what it take's to circulate air in average size homes. The problem is that slow moveing large blades are far superior to smaller fast moving. RPMs are similar to a ceiling fan. A good set up is belt drive,step pulley mounted in gable. There's a formula based on sq ft living area to determine fan size. 36-42-48-52 inch are common sizes. After
installed,speed(cfm)is tweeked using step pulley. Mechanically operated movable shutters are centrally located in ceiling (occasionally two sets for unusual room arrangement). Shutter blades are often insulated and require motor drive to open when fan run's. Right about here is where most people are satisfied but for large homes with several occupants and commercial applications,other options are available. The shutters,cfms and auxillary incomeing outside air openings can be modulated for optimum performance. Some insight on why gable mount offer's advantage. As others point out,evacuating hot attic air is an improvement even if living area isn't. If the fan pressurizes attic space,leaks can occur between attic and living area resulting in dust pushed into living area. Gable mount always results in negative pressure in attic. How much negative pressure? That's where auxillary incomeing outdoor air inlets come into play. With the right bells and whistles,fan can evacuate attic and replace it with outside air from aux soffit inlets while refrigerated air is running.
Few if any direct drive fans can do what it take's to circulate air in average size homes. The problem is that slow moveing large blades are far superior to smaller fast moving. RPMs are similar to a ceiling fan. A good set up is belt drive,step pulley mounted in gable. There's a formula based on sq ft living area to determine fan size. 36-42-48-52 inch are common sizes. After
installed,speed(cfm)is tweeked using step pulley. Mechanically operated movable shutters are centrally located in ceiling (occasionally two sets for unusual room arrangement). Shutter blades are often insulated and require motor drive to open when fan run's. Right about here is where most people are satisfied but for large homes with several occupants and commercial applications,other options are available. The shutters,cfms and auxillary incomeing outside air openings can be modulated for optimum performance. Some insight on why gable mount offer's advantage. As others point out,evacuating hot attic air is an improvement even if living area isn't. If the fan pressurizes attic space,leaks can occur between attic and living area resulting in dust pushed into living area. Gable mount always results in negative pressure in attic. How much negative pressure? That's where auxillary incomeing outdoor air inlets come into play. With the right bells and whistles,fan can evacuate attic and replace it with outside air from aux soffit inlets while refrigerated air is running.
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Fuddy1952
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The original old section of my house has a crawl space underneath. Years ago I had a musty closet smell. My brother who does environmental and remediation work suggested I need negative air pressure there, so at the floor on wall going to crawl space I installed two fans like they use for computers, about 5" ones. They blow from closet out to crawl space which I have a couple vents to outdoors.
That worked.
Many years ago, fans still running and they're quiet.
That worked.
Many years ago, fans still running and they're quiet.
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Fuddy1952
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Neighbor gave me fan after they had a major remodel. The wife likes ac, doesn't like outdoor air. The fan works fine. One blade has a label attic side.
This is probably the best picture. I marked air and arrow with a marker. It blows forward so that's the cupola side. I want hot air going up and out cupola.
MossRoad
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Won't work as it's a door to the basement. A louvered door in that location would mess with the furnace and air conditioning return. I think a vent up high on the interior gable wall to the attic space over the garage would be best in this situation. Thanks, though.
MossRoad
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At my house I've got a small 120V computer fan on a thermostat up in the floor joists that moves air from the room with the wood burner into the other room in the basement. Return air is though a screen door that keeps the cats out of the wood burner room. Works well and is very quiet.
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Fuddy1952
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My parents home built 1949 Dad (rip) had a dining room added in 1963 with a Fisher woodstove. That room got too warm, no circulation so Dad and I put one of those fans near ceiling above stove, then short insulated ductwork around to a vent at bottom of stairs.
It worked fantastic shooting warm air upstairs into bedrooms up there.
It worked fantastic shooting warm air upstairs into bedrooms up there.
California
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Was that attic side when it was mounted between ceiling and attic, or, attic side mounted as a gable exhaust fan?
Deere Dude
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I installed a whole house fan in a hallway and it cooled the house down when needed like it should but I found all kinds of little bugs that got sucked through the screens in the windows. Just stopped using it after a few days of battling bugs in the house.
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Fuddy1952
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My guess ceiling to attic. All I know is air flows direction I marked. My only ? was what's most efficient, blades forward, middle, or back towards motor?