May 16, 2021
Wow 2020 was a challenge! Did you make it through without getting covid? I did not.
NO ATTIC FOR A WHOLE HOUSE FAN?
You have 3 options if you have no attic.
1st, Thorwaldson offers 2 versions of their high flow rooftop mounted whole house fan. One pulls over 8000 CFM through a 24 inch throat, the other pulls 7100 CFM with a 20 inch throat.
2nd, QuietCool offers the same old design they have had for years – a rooftop with a hat on it that reduces its performance – specifically, QC offers just over 3000 CFM vs 7100 and 8000 CFM from Thorwaldson.
3rd, Airscape offers their Direct Vent System – DVS – which is a big fan that mounts on some wall in homes with no attics. It is a good idea but you might not have a wall suited to this.
The reason Thorwaldson can offer so much flow is the patented turbine rain hat – you can see the differences here – and note the Thorwaldson has an optional surround that looks like a chimney to hide the industrial look.
Airscape QuietCool Thorwaldson
DO YOU KNOW WHY MANY SPEEDS ARE VALUABLE?
In the old days we were lucky to get 2 speeds. Then the industry got smart and increased the speeds. Thorwaldson is the leader with the only infinitely variable speed fan on the market. It makes the best use of the modern EC motor (electronically commutated brushless DC motor).
Airscape is also innovative – they designed a 10 speed control that is also very effective.
Why is speed control important? For overnight cooling. In the heat of the day your whole house becomes very hot. If you use a temperature probe to measure your ceiling in the afternoon you will likely see temps from 95 degrees up. That means your roof is even hotter and the joists holding your ceiling up are hotter. If you cool the air in your house it will be warmed up again by the hot ceiling. It takes hours for the ceiling and joists to cool down. So being able to run a whole house fan all night is valuable. Below is the chart of speeds from Airscape. Note that the lowest setting still gives you almost 1400 CFM at a low 34 watts. That costs pennies to run all night. The Thorwaldson speed control offers even lower power.
VentCool’ web site is in disarray
Their web site is very confusing. The home page at ventcool.com shows the models listed below but shows 2 and 3 speeds. Other pages show 10 speeds and the pictures show the fan made by Airscape in Oregon. Here is what the home page says –
Tahoe has PSC motors that take more electricity than EC motors
Summit has the better EC motor and offers 2 speeds and a gravity damper.
Summit S-Class has an ECM and 3 speeds and a gravity damper.
Vista has an ECM and 2 speeds and adds a motorized damper.
July 7, 2020
Airscape is taking the industry lead with designs that are the best in history. Proof of that is in examination of the quality of materials and workmanship in every fan they build. More proof is in the fact that today many other major whole house fan suppliers are rebranding the Airscape designs for sale. Tamarack and VentCool are two examples. On top of that Thorwaldson is now a dealer for Airscape in Southern California. This gives Thorwaldson the ability to offer the best airflow along with Tamarack.
Thorwaldson is the only source for infinitely variable speed fans and the only source for high performance rooftop whole house fans for homes with no attic.
QuietCool has added a new rooftop line but their rooftop uses the old style rain hat that seriously inhibits air flow. The result is that their new Rooftop Mount RM WHF-4.0-DG2 has a motor head diameter of 24.75 inches and pulls just 2,370 CFM at 377 watts. QuietCool continues to offer more models than any other source except Tamarack. They have 2 basic motor offerings, PSC (Permanent Split Capacitor) and ECM (Electronically Commutated Motor). They use the PSC motors in their lowest cost “Classic” line and their dealer exclusive “Trident PRO” line. They use the EC motors in their “Energy Saver” line and their top of the line dealer exclusive “Stealth PRO” line. Their web site says the Classic line takes 117 watts to 1,147 watts depending on model and pulls 1,472 CFM to 6,924 CFM depending on the model. This is an example of the misleading information that QC is notorious for. The CFM of the best Classic fan as tested by the test procedure required by the State of California (HVI-916) is really just 5300.
But what QuietCool is NOT doing is to control all the dealers and stores and installers that sell their fans and that DO NOT put the entire QC performance specifications on THEIR sites. A perfect example is this one on June 19, 2020 – https://wholehousefanexperts.com/ Their logo is
They have offices in Southern California, Sacramento, and the Bay Area so they are serving ONLY California and they are blatantly ignoring the CA Energy Commission rules. The CEC fined SolaTube $55,000 for doing the same thing. You would think the QCGuys would not want to risk a fine like that.
Solatube has emerged as another viable source for whole house fans in just the last few years. They are proud to offer their “Innovative HushMount™ technology for near-silent operation” – which is simply a bracket that holds the fan up on a ceiling joist. Why they use the ceiling when everyone else uses a rafter is not at all clear. And their fans are smaller than any other source – they make 2 models – the larger of which is an 18 inch fan that pulls just 2134 CFM.
But Solatube has run afoul of the State of California just like QuietCool.
Below is the only rooftop mounted whole house fan
Thorwaldson 7000 CFM
Page revised 8-15-20