Quiet Cool questions

[Dukeybootie]

Didn't want to hijack another thread that brought up the Quiet Cool whole house fan so I thought I would start a new one. From what I understand, you wouldn't use them when outside air is undesirable (allergens, smoke, excessive pollutants). Under decent air quality conditions, would they make that much of a difference on the first floor of a 2-story house if the intake vent is all the way on the second floor ceiling?

Also, how loud are they at their highest and lowest settings?

Would they be recommended as a worthwhile component of an energy efficiency optimized home? $2000 seems like a reasonable cost but wanted to get some feedback. Thanks!

 

[jjrandorin]

1. Correct, you would not use it when the air quality outside is poor, or it is hotter outside than it is inside ( except for winter)
2. Yes it makes a HUGE difference in a 2 story home even though the vent is upstairs in a hallway (my exact configuration). Get the right size fan and it sucks air upstairs from everyplace you have an open window.
3. They have DB ratings on their website, but in operation they are quieter than base model AC units (but not as quiet as high end AC units. The noise tends to sound like white noise. The skill of the installer matters here, since they suspend the fan between joists. They are MUCH MUCH MUCH quieter than the old school whole home fans that attach to gable vents.

Yes, wholeheartedly recommend, provided you live in a location where:

1. It cools off some at night, so outside air at night may be cooler than inside the home
2. Its not super humid (not sure about sucking a bunch of humid air into the attic.

It has made a HUUUGGGGEEEEEE difference in comfort in my home, and reduced my AC usage to just the hottest days (like it is right now where I live). I think this is one system that can pay for itself fairly quickly in lack of AC usage. I have their largest fan (the stealth pro 7.0) and it uses around 100w on low (about 700 on high). You typically run it on high for a couple hours in the evening to cool off, then switch to low for the evening.

So even on high, it uses 1/4th of the power of one of my AC units, and I have 2 (each uses 4kWh of power).

In the right environment, these things pay for themselves in like a couple years... probably the fastest return of any of these energy investments (solar, powerwalls etc) that we talk about in this section... provided you have the right environment for it.

 

[BrettS]

Just a quick note that you need to be careful with these fans if you have natural gas heat/hot water. I had a whole house fan when I lived in NY state and while it worked well to cool the house we had issues with carbon monoxide alarms going off at times while the fan was in use. What we finally discovered is that we weren’t opening up enough windows to allow air to enter the house, so the fan was sucking air in through the chimney of our water heater, effectively causing the water heater to vent it’s exhaust to the inside of the house.

 

[getakey]

1. Correct, you would not use it when the air quality outside is poor, or it is hotter outside than it is inside ( except for winter)
2. Yes it makes a HUGE difference in a 2 story home even though the vent is upstairs in a hallway (my exact configuration). Get the right size fan and it sucks air upstairs from everyplace you have an open window.
3. They have DB ratings on their website, but in operation they are quieter than base model AC units (but not as quiet as high end AC units. The noise tends to sound like white noise. The skill of the installer matters here, since they suspend the fan between joists. They are MUCH MUCH MUCH quieter than the old school whole home fans that attach to gable vents.

Yes, wholeheartedly recommend, provided you live in a location where:

1. It cools off some at night, so outside air at night may be cooler than inside the home
2. Its not super humid (not sure about sucking a bunch of humid air into the attic.

It has made a HUUUGGGGEEEEEE difference in comfort in my home, and reduced my AC usage to just the hottest days (like it is right now where I live). I think this is one system that can pay for itself fairly quickly in lack of AC usage. I have their largest fan (the stealth pro 7.0) and it uses around 100w on low (about 700 on high). You typically run it on high for a couple hours in the evening to cool off, then switch to low for the evening.

So even on high, it uses 1/4th of the power of one of my AC units, and I have 2 (each uses 4kWh of power).

In the right environment, these things pay for themselves in like a couple years... probably the fastest return of any of these energy investments (solar, powerwalls etc) that we talk about in this section... provided you have the right environment for it.

I agree.

I mentioned this on the other thread, but if your house is well insulated, it will keep heat in at night rather than cooling down. The fan pushes the hot air out and pulls in the cool. Made a 10 degree difference for us. Last night, outside low was about 65 (after a daytime high of 94) and house cooled to 71. Without the fan, house would stay about 78 with no AC on

 

[Dukeybootie]

If I figure correctly, the whole house fan will be used mostly on summer evenings and nights then. Or maybe when there is a lot of cooking smoke we want quickly evacuated. Or any time we just want to replace inside air with outside air for any other reason. Does this leave it mostly on standby in the colder months when heat is on, essentially making it a one or two season device for someone in Southern CA like me? Wondering if there are other good reasons to run it that are not usually considered.

 

[jjrandorin]

If I figure correctly, the whole house fan will be used mostly on summer evenings and nights then. Or maybe when there is a lot of cooking smoke we want quickly evacuated. Or any time we just want to replace inside air with outside air for any other reason. Does this leave it mostly on standby in the colder months when heat is on, essentially making it a one or two season device for someone in Southern CA like me? Wondering if there are other good reasons to run it that are not usually considered.

I have only had mine for a couple of months, but someone in my general area (@Uncle Paul ) mentions they also work well in the winter to pull warmer air inside when it might be colder.

The best way to think about it, is that the unit creates a windy day pulling air into the home from outside, when there is no wind. Air exchange is always good, as many people (me included) tend to "hole up" for long periods of time normally. In my area the breeze is in the afternoon to early evening, but during the summer its hot then, so you dont want outside air in the home. By the time it cools off, its "still" outside , but this device pulls air inside at a nice clip.

The only real learning curve is figuring out which windows you want open, and how many you need to open to get the desired airflow (less windows open = more air from the fewer windows that are open. You create more air movement opening a window a little than a lot, but its something that depends on your fan size and your home.

 

[Uncle Paul]

You rang?
Fan has louvers that close tightly when not in use. This effectively seals off the attic and gives complete control. Many days I do not use it at all, just like AC or Heater. It is a tool that owners learn how to best use.
If it is a cold wintery day, it is normally not used, but if the outdoors raised above house ambient in the afternoon then you can bring in some free, welcome, warmth.

A side benefit is that you can open a screened door or window near where you are sitting and feel a pleasent cooling breeze when the CC is running. This often is enough you will not need to turn on your AC to remain comfy.

It is kind of like opening and closing your blinds to take advantage of solar warming. Some will not feel it worth the bother, but if you are Eco or frugal, it is an easy way to avoid using the heater or AC.

Simply, it makes opening a window about 10X more effective. If you have great breezes and flow through your house, then the fan is probably not that necessary.

Usually guys are more active in optimizing it's use, expecially if they are the ones paying the bills.

The fans are quiet enough that they do not disturb sleeping. It is a pleasant soft sound that we do not find to be objectionable.

Quiet Cool has thousands of installers, expecially in areas where the climate is most conducive for their use. They are happy to visit your home and do an evaluation as to their effictiveness. They will check your attic for proper ventilation, and will notify you if additional (extra cost) vents would be required to make their systems effective.
They carry about 10 different sizes and configurations with 1, 2 or 3 speed controllers. They can be adjusted by convenient wall switch or even more convenient app. They cannot be turned on when away from your house, as someone needs to be sure a window is open for them to circulate air. If a window is not open, then the fan will tend to such air through any inlets like electrical sockets or chimneys.

It is kind of like the old days when you needed to crack a window in your car to make the heater work better. Modern cars are not so tightly sealed, so no longer necessary to crack a window. This is why it was often hard to slam shut the doors in VWs as they were so tightly sealed the air inside the car had no place to go and would compress.

For many climates they are super cost efficient, for others not so much.

 

[jaed]

This might be a bit complex and DIY.
Here is something I did. I put a automatic damper in my return air. Then put a Y in the branch with another damper and from that damper I put a hole in the roof to the outside. Then wired it up to a switch so when I turn it on and tell the HVAC unit to run fan only it will close the normal return and open the outside air. We run it all night. The wife loves it because the AC unit is really loud.

That was in my old house now this house I wired up a relay so it kills the signal to the outside condenser so we can make it turn on and off like a normal AC unit from out Thermostats. Then also did the same for the exhaust side so we didn’t have to open a window to release the static pressure.

 

[Uncle Paul]

This is essentially what the Quiet Cool does. Except you do not need to put another hole in your roof.

Friend uses his QC in the evenings because his noisy AC unit is right outside his bedroom window. Almost silent as he put QC ceiling vent down the hall. (He has a single story home)

No reason to overthing these units. It is similar to the Whole House Fans people have been using for 60 years, except it does not sound like a helicopter is landing on your roof.

The QC fan is suspended by rubber straps from a rafter. Totally isolated from your framing.

 

[hurjio]

My opinions:

• They really can move a lot of air, even if your fan is in 2nd floor hallway. You just have to be strategic about which windows/doors you're opening. Want to cool downstairs? Only open downstairs windows/doors.
• I have Stealth Pro model. On low speed, it is a barely noticeable hum. On high it's noticeable, but nothing that would impede conversation or TV volume downstairs.
• They are nice to exchange the air in the house with fresh air.
• Obviously, they don't do anything if it is hot outside. Thus, you will most likely be using this starting around an hour before sunset or so. If you don't run it all night, you can run it for a bit first thing in the morning to pre-cool the house for the day.

 

[MJ_CA_2019]

This is essentially what the Quiet Cool does. Except you do not need to put another hole in your roof.

Friend uses his QC in the evenings because his noisy AC unit is right outside his bedroom window. Almost silent as he put QC ceiling vent down the hall. (He has a single story home)

No reason to overthing these units. It is similar to the Whole House Fans people have been using for 60 years, except it does not sound like a helicopter is landing on your roof.

The QC fan is suspended by rubber straps from a rafter. Totally isolated from your framing.

I have one of said helicopter whole house fans. I love the effect, but it is in my boys bedroom on the second floor and they don't like it.
I installed a manual timer switch so I can run it for 1 or 2 hours after we get up but am interested in stepping up to more "Smart Home" style because i'm not getting the coolest part of the day.

Current opening is in the bedroom ceiling roughly 32" by 27" and it's the drop in style where the fan is right by the louvers.

Alternatively, or maybe in addition, I have two other attic spaces that are over the first floor. One is our master bedroom / office suite and the other is a laundry room (shares attic space with our garage). Our house is two story in the middle kind of rectangle, with area on ether side that are only 1 story which is why we end up with the additional attics.

How important would it be to pull the air out of those other two attic spaces? In terms of CFM I think our current setup on the 2nd floor pulls enough air to cool most of the house, but I'm wondering if maybe two small QC units would make things even better.

I appreciate any insight you have around making my current unit "smarter" and thoughts around the other attic spaces.

 

[Carbonfiber]

Thanks for starting this thread up! It was brought up in one my threads and caught my interest as well! Definitely following this one.

 

[Alonzo]

As a child in SE Texas, I grew up in houses with attic fans before the days of air conditioning. They do help to cool the house in the evening and at night. What I remember most about them is how much dust they brought into the house.

 

[kardiff_kris]

I pulled the trigger, I’ll post photos/thoughts after the install.

 

[Uncle Paul]

Make sure you have screens on the windows and doors you open to get fresh air. Don't want to suck in all those little buggies

 

[Uncle Paul]

To draw hot air out of your single story attics you can install simple thermostatic fans in a gable. Will turn on when the air is superheated, then shut off when ventilated.
Your Quiet Cool installer can remove your helicopter fan and replace it with a suspended QC. Probably also be able to install the thermostatic fans the same day. These guys are in and out in just a few hours. Got the installations down.

Bonus use for me is that Wifie sometimes smells up the kitchen when cooking yummy food. Turn on the fan, open a nearby window and the smell goes quickly away

 

[jjrandorin]

I have one of said helicopter whole house fans. I love the effect, but it is in my boys bedroom on the second floor and they don't like it.
I installed a manual timer switch so I can run it for 1 or 2 hours after we get up but am interested in stepping up to more "Smart Home" style because i'm not getting the coolest part of the day.

Current opening is in the bedroom ceiling roughly 32" by 27" and it's the drop in style where the fan is right by the louvers.

Alternatively, or maybe in addition, I have two other attic spaces that are over the first floor. One is our master bedroom / office suite and the other is a laundry room (shares attic space with our garage). Our house is two story in the middle kind of rectangle, with area on ether side that are only 1 story which is why we end up with the additional attics.

How important would it be to pull the air out of those other two attic spaces? In terms of CFM I think our current setup on the 2nd floor pulls enough air to cool most of the house, but I'm wondering if maybe two small QC units would make things even better.

I appreciate any insight you have around making my current unit "smarter" and thoughts around the other attic spaces.

The quiet cool fans might work in your situation, but at least the installer I used (based out here where I live but services all of southern california) also takes into account how much venting you have. If you install "too much" fan(s) without enough venting, the air has to go "somewhere" and will then go down your walls, which isnt what you want.

different homes have different type of roof venting. My home has vents called "o'hagin" vents which are panels in the roof. I dont have a gable. I think what you would want to do is contact one of the installers, and have them out to take a look and make a recommendation.

There are all sorts of companies that install these. I was really happy with the one I went with. So as not to shill for a specific company I wont post it, but if you are interested in the name of the company shoot me a PM and would be happy to share.

 

[ddawson]

I have a large Quiet Cool Fan and two solar roof mount fans,

Works great to lower the temp in the whole house in the morning,

 

[wwu123]

For the DIY crowd, I noticed econfort.com has the ES-3100 model at $599 about 30% off, probably end-of-season sale heading into fall:

QuietCool QC ES-3100 - 3,081 CFM - Energy Saver Advanced Whole House Fan

The green ones have the more efficient ECM motor, doesnt save much power at full speed, but you can run it all night at lower speed for a fraction of the energy.

Good for CA and southwestern climates where it cools off at night. I was able to ride through the record CA heat wave a few weeks ago with no central A/C, with just this at night and one portable hose A/C during the day for a 2600 sq ft house..

 

[MJ_CA_2019]

How do the thermostats on these things work?

If it's 107 outside the fan could run constantly and never get the attic down to the desired temp.
Conversely, if it's 95 in the attic, how does it know that the outside temp is colder?