Whole House Fan - So far so good.

UncleDave

$50 Site Donor 2023
Joined
Jun 2, 2014
Messages
7,679
Location
Ca.
With 2 full months of 90-100 degree days, but nights in the 60's with low humidity I started running tests with box fans in windows at night on the second floor to really great results.

Bought the big 6500FCM Centric Air Whole house fan and have been really happy with it. It can blast clear the air in the house on high in a few minutes and is barely perceptible on low where it runs at night.

I need to work on a better mount as Im pinching the duct but it still flows tons of air.

Its great waking up in the morning to a chilly bedroom filled with fresh country air for far less than even my super efficient 21 seer variable speed unit.

IMG_3100.jpeg
IMG_3092.jpeg
IMG_3096.jpeg
 

UncleDave

$50 Site Donor 2023
Thread starter
Joined
Jun 2, 2014
Messages
7,679
Location
Ca.
That's how I grew up; no A/C in our first two houses. Fan works tremendously.
That also was back in the day where the front door was left open all night with a screen door, so air could move throughout.

A box fan push pull combination work really well as well and the white noise is just awesome for me.
Reminds me of childhood comfort when you slept the sleep of angels without the ever-present worries of adulthood.

We had Ac everywhere I lived, but we never wanted to run it to save money.

Both central air in the "new" house built in 70, and the old houses had giant through wall units that ran on 220.

In the midwest we spent as much of the evening and afternoon if the basement to be cool, but running dehumidifiers which in a cool basement is an air conditioner.

People in Cali dont even know what a basement is.
 
Joined
Feb 14, 2017
Messages
156
Location
Michigan
I have one in my 50's ranch. I absolutely love it, Hums away all night and i sleep like a Baby. AC dosen't come on untill late in the afternoon.
 
Joined
Mar 4, 2017
Messages
24,784
Location
...
It does today -it vents to the gable ends outside, but In a month or so I'll have a roof ridge above to vent directly outside.

Im torn on this as it cools the attic space the way it is.


I was thinking that the attic would get hotter as you pulled heat from the house and into that space. I want to do something similar at another house but I have no gable ends or vents so it would vent out the soffit eaves in my plan.
 

dishdude

$100 Site Donor 2023
Joined
Nov 14, 2008
Messages
14,259
Location
Phoenix
I was thinking that the attic would get hotter as you pulled heat from the house and into that space. I want to do something similar at another house but I have no gable ends or vents so it would vent out the soffit eaves in my plan.

The air in the living space being pushed into the attic is going to be a lot cooler than the attic air.
 

UncleDave

$50 Site Donor 2023
Thread starter
Joined
Jun 2, 2014
Messages
7,679
Location
Ca.
I was thinking that the attic would get hotter as you pulled heat from the house and into that space. I want to do something similar at another house but I have no gable ends or vents so it would vent out the soffit eaves in my plan.
The heat in my attic is always way hotter than the rest of the house- and the attic holds that heat a looooong time.

The WHF is a twofer - it pulls the outside air into the house and cools the attic way down buying me more time before needing Ac the next day and in the case of mid- high 80's days not at all. Exactly what Little Lebowski is describing.

As long as your eaves are clean it'll do the same thing for you- just vent differently.
 
Joined
May 7, 2004
Messages
13,157
Location
Nokesville, VA
You are very lucky to have nightime lows in the 60's, down here it was 85 at 4:00 AM!

When the nightime lows are in the 60s here, it's so humid out that by morning all the windows in the house will be covered with dew.

But at least the AC uses a full 1kW less running at 65F outdoor than it does at 90F outdoor. That's on top of moving more BTUs so the discharge air temp is lower.
 

UncleDave

$50 Site Donor 2023
Thread starter
Joined
Jun 2, 2014
Messages
7,679
Location
Ca.
You are very lucky to have nightime lows in the 60's, down here it was 85 at 4:00 AM!

They even claim that ridge vents and attic fans are useless here.
Yeah I'm at 1500ft in the sierras Im in a valley but still get some mountain breezes and mostly cooler night.
We've only had a couple of 75 degree nights but we do get them.

Seems like an attic fan would buy you "some" cooling depending on what your attic gets to , but a whole house wouldn't work well.
 

UncleDave

$50 Site Donor 2023
Thread starter
Joined
Jun 2, 2014
Messages
7,679
Location
Ca.
When the nightime lows are in the 60s here, it's so humid out that by morning all the windows in the house will be covered with dew.

But at least the AC uses a full 1kW less running at 65F outdoor than it does at 90F outdoor. That's on top of moving more BTUs so the discharge air temp is lower.

Yeah not great for WHF.
 

UncleDave

$50 Site Donor 2023
Thread starter
Joined
Jun 2, 2014
Messages
7,679
Location
Ca.
Had a WHF in a previous house and loved it. On the list to add to this house. Only downside is if a skunk discharges upwind in the neighborhood it fills the whole house before you can shut it down. Been there quite a few times. Ugh.
already happened - it very efficiently skunked the whole bedroom - woke me up.
 
Joined
Jul 9, 2008
Messages
3,592
Location
British Columbia, Canada
In Saskatchewan in the late 1970s/early 1980s they used what was called poor man's air conditioning. Houses had a thermostatically controlled fan in the gable end of the attic or a fan mounted in the roof itself. The fan would come on when the attic got hot and draw cooler air into the attic space through the soffits. I don't know if they still use them and if not, why not.

A doctor who had worked in India said they had a sprinkler on the roof. Evaporation of the water would have a real cooling effect.
 
Joined
May 7, 2004
Messages
13,157
Location
Nokesville, VA
In Saskatchewan in the late 1970s/early 1980s they used what was called poor man's air conditioning. Houses had a thermostatically controlled fan in the gable end of the attic or a fan mounted in the roof itself. The fan would come on when the attic got hot and draw cooler air into the attic space through the soffits. I don't know if they still use them and if not, why not.

Probably doesn't help as much if there is a ridge vent and plenty of soffit venting (like the vinyl soffit vent used on newer houses with holes in it vs. the older houses that had a wood soffit with vents added every few feet).
 

UncleDave

$50 Site Donor 2023
Thread starter
Joined
Jun 2, 2014
Messages
7,679
Location
Ca.
In Saskatchewan in the late 1970s/early 1980s they used what was called poor man's air conditioning. Houses had a thermostatically controlled fan in the gable end of the attic or a fan mounted in the roof itself. The fan would come on when the attic got hot and draw cooler air into the attic space through the soffits. I don't know if they still use them and if not, why not.

A doctor who had worked in India said they had a sprinkler on the roof. Evaporation of the water would have a real cooling effect.

What you are describing is simply known as an "attic fan."

I have one of those as well - it kicks on at 105 and runs till the attic hits 85 pulling in outside air.

A roof sprinkler would be awesome.
 

UncleDave

$50 Site Donor 2023
Thread starter
Joined
Jun 2, 2014
Messages
7,679
Location
Ca.
95 yesterday - 64 at night humidity in the 30's.

Master bedroom and most of the house was 64 in the morning - super crisp and awesome.

Loving this thing although you have to manage/direct the airflow a bit by closing off this or that window.

The second story ends up within a degree or so the ground floor WITHOUT bothering to open any of its windows which would reduce volume from the lower floors anyway.
 
Joined
Apr 22, 2018
Messages
2,321
Location
MA
As I sit in my beautifully conditioned A/C home the key to your plan is the low humidity. Today it was 94F and 38% humidity during the day but it was 79F and 79% humidity at 9:30 PM. Inside it's 68F and 50% humidity and I'm covered in a blanket watching TV...lol.
 
Top