Recently we have been using our new and improved sound testing chamber to make sound comparison videos of our different models. The shooting of these videos reminded us that the set up of the ducted models will make a significant difference in the CFM and noise levels. Basically, improper installation will decrease the unit CFM and increase the amount of noise. Some numbers for comparison:
AirScape 4.5 improper installation – high 59 dBA / low 50 dBA
AirScape 4.5 proper installation – high 55 dBA /low 46 dBA ……A 4 dBA difference!
The photo above shows the correct install dimensions for the 4.5 WHF. You will notice that we have a nice even bend and the ductwork is fully extended (Note that we used an extra length of the provided chain to help support the bend). It is important to maintain the 20″ diameter of the duct through the 90 degree bend. This will ensure that you get unrestricted airflow through the duct and will help disrupt the sound waves. You also want to make sure the duct and fan are fully extended from the 90 degree bend. This moves the fan to the furthest point from the grill opening, thus decreasing the decibel level.
Airscape 2.5/2.5e installation: The install dimensions for the AirScape 2.5/2.5e are very similar. The duct should be 21″ from the attic floor. It should extend 44″ from the 90 degree bend to the fan (you may be able to extend it to 48″ if the bend is supported as shown in the photo above). The top of the fan should be 44″ from the attic floor.
At long last! Southern California Edison, the only remaining utility company still needing to update their rebate list to include our 2.5 and 4.5 models, has finally done so. Good grief, it took them long enough! For over 6 months now I have been making at least one, but usually more, pleading calls a week to their rebate center and rebate program manager. I’ve sent more 
than a dozen emails to them. I’ve begged anyone over there who would listen to look at the California Energy Commission appliance database and the PG&E website for the required documentation, which are the only requirements listed for SCE to list a new product model.
It wasn’t the rejection that bothered me the most, although 6 months with no response is disheartening to say the least. What bothered me most was when customers would call us, frustrated at receiving a rejection to their rebate application, who had been told by the SCE rebate center that their list was absolutely up to date with no pending items. No pending items? What do they call over half a year’s worth of unanswered voicemail messages and emails then?
Well, all my bitterness aside, I am happy to announce that the long wait is over. Every model whole house fan that AirScape manufacturers is now listed on the SCE’s list of qualifying products. SCE qualifying product list
For a list of the other utility companies that offer rebates on our fans, see our rebate page. AirScape rebates
“When you have a hammer, everything looks like a nail”
What a wonderfully simple way to describe much of our world. I am reminded of this whenever I see people working on the “energy” problem. Software people clearly know, that if only we wired everything up and monitored our energy use, the rest of the problem would be trivial. Economists clearly have the upper hand, because they can describe carbon trading as the sure fire method to reduce carbon output, increase energy efficiency, and still have economic growth. Photovoltaic manufacturers, electric car builders, and wind farm developers are among the many queuing up at the public feeding trough.
Nothing wrong with any of those solutions. Just bear in mind the aphorism.
By the way, our hammer is a whole house fan.
The newest version of our control board has a master override or interlock. The interlock, which is now required by some building codes, effectively disables the WHF by closing the damper doors and turning off the fans. It is often used in conjunction with smoke detectors or mechanical systems located in the attic. The idea is that if the furnace turns on or the smoke detector goes off the WHF will shut down. This could slow down the spread of a fire or save $$$ if the furnace was accidentally turned on.
The interlock is integrated into our 24v digital controls on V4 of our control board. To use the interlock simply remove the two-pin shunt and run low voltage wire from the interlock screw terminals to the relay on the device that will disable the WHF. To activate the interlock the relay should interrupt the 24v current. Do not wire 120v to the interlock.
When activated a solid red LED will illuminate on the WHF control board. The fans will turn off and the damper doors will close. Once the interlock is disengaged, the LED will go out. The WHF can be restarted by flipping the wall switch off and on again or by using your remote.
When you call in with a tech support issue we will want to know which version of our control board is controlling your unit. This is important because it will help us properly diagnose what is going on with your WHF. In most cases we can determine the control board version if you give us the model information for your AirScape. The model is listed on a sticker found on the unit (near the junction box on the 1.7, 2.5, 4.5 and on the damper door of the 1.0). Occasionally the model sticker isn’t enough. If you are already going into the attic to write down the model information you might as well take a look at the control board as well.
The control board has had several different incarnations over the years. Please take a look at the photos below and identify your control board before you call tech support.
My control board looks most like: 1, 2, 3, 4, 5 or 6 (Differences between 3 and 4 circled in red)
1
2
3
4
5
6
