attic fan, attic fans, solar fan, solar powered attic fan, power attic venting, gable fan, attic venting, energy conservation,german attic fan, ventilation


Phoenix, Arizona 85022

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Powered Attic Venting
 

POWER VENTING

The importance of venting your attic cannot be overlooked.  In cold climates, improper venting can lead to moisture build-up which causes mold growth, wood rot in extreme cases or even ice in the attic insulation. In hot dry climates, stagnant air can dry out your trusses, increase your energy costs for air conditioning and make your house uncomfortable. 
If your home is like most that we inspect, it is severely under vented.  You can add more soffit and exhaust vents but at what cost?   Power venting may be a more cost effective and  efficient method of achieving your goal.   However, venting is just part of the problem.   A well ventilated attic will reduce the convective load.  The largest component of heat gain or heat loss in any home is infrared heat.  Control this and you can really save! 

We have found in our full scale testing of homes with a radiant barrier installed that passive venting is not sufficient to remove the millions of BTU's changing direction from the reflective surface and that power venting is required. 

Solar Fans:  Sounds like a great idea right?  Sun comes up, creates free energy, spins a fan to remove the hot air from the attic.  In theory this makes sense.  The reality however is much different.  Question:  "At what point during the day will the solar fan put out the most amount of power?"  (assuming a Southern exposure for the PV panel). Answer:  Solar noon. Next question: "When does the attic require the most amount of venting?"  Answer:  Between 1:30pm and 7pm.  When the attic requires the most amount of venting the solar fan is putting out the least amount of power. 

  We import a vibration free, powerful, reliable powered attic fan manufactured in Germany.  This attic fan is unlike any other available:  quiet, powerful and very efficient.
We include an adjustable thermostat and an optional mounting box with this system.  This fan features an external rotor to which the fan blades are welded.   This unique design reduces blade flex and vibration and eliminates one of the shaft bearings. 
The bearings are sealed and never need attention.  Install it, set the thermostat and forget about it.  The 14" fan consumes 245 watts.  At a national average
of .10/kwh running for eight hours a day  that's less than $6 per month.  There are sites on the 'net that say the power consumption of an attic fan does not offset the cost of running it.  The goal is keeping your A/C off as much as possible which consumes 1600 watts per ton.  Logic would dictate running a fan for $6/month would be preferable to longer run times on your A/C unit from the stagnate, overheated attic air and the load on your ceiling.

 

 

 Click here to see what our customers have to say about this product and our service.

 


This shows a typical home store attic fan installed on a gable vent inside the attic.  Although the mounting looks secure, the application is incorrect since the space around the fan is not blocked off.   The fan will create a negative pressure behind the fan and will draw air from the closest point, in this case, from vent openings around the fan.
This means very little air will be exhausted from the attic and most of it will be drawn in around the fan.  
The open area around the fan shroud (the round ring), needs to be blocked off with cardboard or wood to make this type of installation effective.  We see this type of installation on almost every home that has one!  The following are examples of what not to do!

 

 

 

 

 

 

 

This is the 14" German fan mounted before the area around it has been blocked off with cardboard.

The installation seen above was installed by an engineer.  This will have virtually no effect on 
exhausting air from the attic at the opposite end since most of the air will be entering around
the fans.  As you can see he also installed fiberglass up against the roof decking which will
only serve to store tremendous amounts of heat all day, cook his roofing system then allow
it to dissipate long after the sun goes down.  The people who bought this home had $475/mo
energy bills for a 1500 sq foot home.             

                     

Here is a roof mounted German fan mounted where a Home Depot fan used to be. 
The dome shaped attic fan cover on the roof has been replaced with the correctly sized
Aura Vent.

 

Two 10" fans mounted side by side.  Choose this option when a large vent is not available.

To place an order click here

Warning: In homes that have gas appliances such as water heaters or furnaces in the attic, great care must be taken to insure adequate intake venting is provided (gables/soffits), so as to not create a negative pressure that will draw fumes down the chimney of gas appliances.   Installing an attic fan in this application has the potential for fire or filling your attic with carbon dioxide.  Just make certain there is sufficient intake openings to circumvent this situation.      

Performance Data

Fan
Model
RPM Volts Max.
Watts
Max.
Amps
0" .100" .125" .25" .375" .5" Sones**
8" PAV 1550 115 45 0.41 304 246 224 74 - - 4.1"
10" PAV 1500 115 68 0.62 624 558 533 377 132 - 7.9
12" PAV 1400 115 130 1.19 1208 1069 1030 797 - - 9.4
14" PAV 1200 115 245 2.24 1839 1654 1599 1295 - - 9.6
16" PAV 1400 115 458 4.19 3054 2882 2839 2570 2198 1699 12.0
18" PAV 1550 115 698 6.39 4115 3895 3840 3549 3239 2908 14.3
20" PAV 1100 115 435 3.98 3693 3368 3279 2775 1429 - 10.7
20" PAV 1450 115* 916 8.39 4949 4682 4615 4274 3917 3445 16.4
22" PAV 1000 115* 756 6.92 5629 5248 5153 4432 - - 12.
25" PAV 1000 115* 1134 10.38 7858 7355 7230 6567 - - 14.8
** The sound ratings shown are loudness values in fan sones at 5ft. (1.5m) in hemispherical free
 field calculated per AMCA Standard 301. Values shown are for installation Type A: Free inlet fan
 sone levels. All sone values shown are calculated at 0.1" (static pressure in inches W.G.).


Specifications
Unit sizes and dimensions
fan size specifications

Fan Mounting box dimensions:

8" fan: Mounting box is 10"x10"x4" with a 1.5" flange

10" fan: Mounting box is 12"x12"x4" with a 1.5" flange

12" fan: Mounting box is 14"x14"x4" with a 1.5" flange

14" fan: Mounting box is 16"x16"x4" with a 1.5" flange

16" fan: Mounting box is 19.5"x19.5"x4" with a 1.5" flange

Construction Features

   No maintenance required     The 14" fan has twice the power (and capacity), of a home store fan