Do Solar Attic Fans Really Help

If the angle of the sun is lower in the sky morning and late afternoon or the sun s rays are trying to cut through thin clouds or haze the fan spins slower moving less air.

Do solar attic fans really help. Yes the solar powered attic fans spin at different speeds. Do attic fans really help to cool a room. Using the simple physics principle of air circulation it can draw in cool air while letting out the warm air. One reason power attic ventilators don t help in my original article i focused on makeup air.

Solar powered attic vent fans usually don t move as many cubic feet of air per minute cfm as hardwired fans. If a cloud blocks the sunlight the fans slow or stop. Solar attic fans can provide your home with an improved appearance that speaks of environmental consciousness when you make this investment. For the attic fans to work at peak efficiency they need to be on a south facing roof slope if you live in the northern hemisphere.

This pressure balance improvement and the cooling provided by the air flow are most significant in the case of a leaky ceiling. Exhausting moderate amounts of attic air as solar fans do can counteract this reducing infiltration my calculations show it to be about right for a vented attic but either do the calculations or measure the pressures. Solar attic fans work by pulling in the cold air from the soffits and pushing out the hot air that has accumulated at the top of the attic. Yes attic fans can make a difference.

Attic fan savings claims. But they re much easier to install since no wiring is needed. A significant amount of that cooling is likely to come from conditioned air being sucked up from the house below. Cold air is at the bottom and warm air is at the top.

However the utility of attic ventilation fans is actually quite a controversial topic. The single solar powered attic fan i have has not lowered the temperature in my attic at all. This is basically how air naturally moves. The point of having an attic fan is to lessen the load on your ac system saving you money.

The attic fan just helps the air move more which adds cooler air circulation. That is i said that when you run a power attic ventilator in a typical house yes it will cool the attic down. Good insulation reduces fan effectiveness. In addition to soffit gable and or ridge vents you may want to add a power vent fan to your attic to increase air circulation.

To determine the number of cubic feet per minute needed for a power vent fan multiply the number of square feet in your attic by 0 7. This backdraft can bring dangerous and toxic fumes into your home like carbon monoxide an odorless and deadly gas. Attic ventilation fans whether hard wired or powered by their own solar panels seem like a low cost and effective way to help keep your house cool. Attic fans can create a negative pressure condition in your home causing vented appliances to backdraft.