to make sure this fits.
Industry Leading 25-year limited warranty on entire unit.
Highest quality materials in any Solar Attic Fan on the market.
Easily installed with No wiring required.
Optional snap-on thermostat for use in colder climates (sold separately).
All necessary installation hardware included.
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Solar Attic Fans are easily installed on pitched Fiberglass-Asphalt Shingle roofs and are a great product for proper attic ventilation. Natural Light brand solar attic fans are top rated by builders and are of the highest quality built in the USA. The DC motor is powered by the included 36-watt solar panel with the attic fan motor moving hot air and moisture out of the attic space everyday. Solar panel is adjustable from flat up to 45 degree angle.. Solar Attic Fans mount on 3/12 to 12/12 pitch roofs. (this unit is not for flat roofs or side wall mounting – Flat roof mount models are available). Moves up to 1628 cubic feet per minute. Use one attic ventilation fan for every 2625 square feet of attic space. Note: Optional Thermostats and Fire Safety Switches are sold separately. For installations on Tile roofs optional Turret extension and Tile Roof Flashing kits are sold separately. Made in USA.
|Item Weight||30 pounds|
|Product Dimensions||27.2 x 27.2 x 11.5 inches|
|Item model number||SAF36B-FL|
|Material||Aluminum, stainless steel, glass|
|Maximum Power||36 watts|
|Item Package Quantity||1|
|Air Flow Capacity||1628 CFM|
97 customer reviews
4.5 out of 5 stars
|Best Sellers Rank||
#17,626 in Tools & Home Improvement (See top 100)
|Shipping Weight||39 pounds (View shipping rates and policies)|
|Date First Available||May 20, 2010|
Product Warranty: For warranty information about this product, please click here
June 12, 2015
September 6, 2016
NOTES & MY LEARNINGS FIRST: I live in an 18 year old, two story 3300 SF home with gray, flat CONCRETE tiles on the roof, in Cupertino, CA (zip 95014). My attic’s volume is ~1500 SF. Installation was done in July ’16 by myself. Fan comes on around 10-11am daily when the attic temp reaches 80 degrees. After sunset, it intermittently cycles for 15 mins every hour until the wee hours of the morning and the attic’s temp drops to the 60s overnight. Once the temp drops to 77 degrees, the thermostat no longer has the fan cycle. Relative humidity in our attic ranges from 20% to 30% depending on the time of day. Attic temp peaks between 4-5pm daily (July/Aug). If I keep the attic access door in our hallway open and open up the upstairs windows all day, I can drop the attic’s daily peak temperature by another 3 degrees, which is how I know our attic can benefit from more intake vents.
Through measuring my attic’s temperature hourly throughout the day, I confirmed that my attic remains hot for hours after the sun sets. This may be true for most attics. Here in the Cupertino, we don’t have that many days above 95 degrees, but our 2nd story bedrooms can remain hot on the 95+ degrees hottest days until 10pm. In the pictures are the net temperature differences in my attic before and after the fan installation. Before that though, here’s what I did to modify my solar fan to continue cooling after sunset…
This fan is great, but I wanted more!
Natural Light’s 36 watt solar attic fan (model SAF36B-FL) doesn’t have a feature that I really wanted….a way to have it continue cooling my attic even after the sun goes down. (I thought I’d have to make my own circuitry to do that.) I really like that unique feature of the US Sunlight fans using their optional Solar Control (model #SC20), so I bought both and made some easy wiring modifications to make them work together. I preferred the Natural Light fan due to its high Amazon rating but also wanted the other company’s “cool” functionality (see what I did there?) of their Solar Control. It switches between solar power and AC power depending on sunlight availability (after sun sets), has a remote control for the fan (always on or thermostat controlled), and a remote LCD display showing attic temp/humidity. At first, I wasn’t sure if they’d work together, but after doing it, I now know it works and I have the best of both worlds…it’s now perfect for my needs! =) I’ll share how I did it:
Re-wire the fan so that the Solar Control acts like a thermostat. Instead of having the red/black wires from the fan’s solar panel going straight to the motor, I have them going to the Solar Control instead. The wiring connectors had to be cut and spliced (cut off the spade plugs and solder the wires on to the Solar Control’s cables), but that’s all it took! 10 mins and done!
Here are some things that weren’t documented anywhere but I discovered them during my project. They’ll help you should you want to do this too:
* The Natural Light 35 watt solar attic fan’s solar panel’s output is 20 volts DC. With full sunlight, the fan motor draws 1.8 amps. (36 watts = 20 VDC x 1.8 amps)
* I purposefully bought the bigger model fan (36 watts) since my attic has multiple levels/pockets of air, figuring I’m less likely to have buyer’s remorse if the purchased fan is too strong. I can easily slow down the fan speed by covering up a portion of the solar panel. Slowing down the motor by shading a small portion of the solar panel works perfectly.
* It turns out that covering up only ~5% of the panel from sunlight results in the fan RPM slowing down to roughly 2/3 speed….perfect if one wants to “dial in” the right amount of attic suction without creating a negative pressure in there. The voltage/current draw is reduced accordingly.
* The Solar Control outputs 18 VDC to the fan, so I had a pretty good sense pre-purchase that they’d work together despite US Sunlight telling me that their device works only with their fans (both devices’ operating voltages are within acceptable/compatible range of each other). Whether at the full 20 VDC output of the panels or at a reduced voltage, the two work fine together.
TEMPERATURE DIFFERENCES BEFORE AND AFTER THE FAN INSTALLATION:
I recorded the daily PEAK attic and outside temperatures so that I could see how much the fan is helping. I wanted to know the “baseline” temperature before so that I could justify the cost and effort. Attached is a screen shot of the chart I created, but basically, the fan dropped my attic temperature by an average of 6 degrees on days that had a varied outside temperature of 76 to 91 degrees. I’m happy that the fan helps keep our attic cooler, but I have to say that it would have been hard to know for sure w/out taking before-and-after measurements.
I’m concluding that some online reviews of “…house feels cooler…” may contain some wishful thinking (avoiding post purchase cognitive dissonance–there, I used that term I learned way back in college!) Your mileage may vary so don’t expect a single fan installation to make your house cooler necessarily. I do not regret buying and installing this fan, because I learned A TON about attics, roofs, temp patterns, etc from the experience.
I should note that prior to installing this fan, my attic did not have ANY exhaust vents–a pro roofer discovered this while giving me a fan estimate and told me the builder probably actually forgot! My attic temp drop would be 9 degrees (additional 3 degrees drop) if my attic had adequate intake vents.
August 3, 2016
But since was Amazon if it did not work as described I could get my money back, plus the thing has a 25 year warranty.
Within 15 minutes of the fan being turn on, the house temperature went from 95 to 76. I am still doing the happy dance. This thing is the greatest. I LOVE it.