Attic Fan Power Consumption

A more helpful comparison may be to an air conditioning unit.

Attic fan power consumption.

During workdays would leave air conditioner off when leaving in the morning. You could run 30 fans using 50 watts for the same power consumption. As you can see the consumption correlates to the wattage of the appliance. The net free area of a vent takes into account the resistance offered by its louvers and insect screens.

Consider a space heater which will use roughly 1 500 watts per hour. However if your attic has blocked soffit vents and is not well sealed from the rest of the house attic fans will suck cool conditioned air up out of the house and into the attic. After attic fan installation ac still off during day. Attic fan ventilation attic fans are intended to cool hot attics by drawing in cooler outside air from attic vents soffit and gable and pushing hot air to the outside.

You ll need 2 to 4 times the normal area of attic vents or about one square foot of net free area for every 750 cubic feet per minute of fan capacity. This was observed on numerous days following the installation. Temp 92 f at 5pm. Not many appliances in the home consume as little power as a fan.

Energy usage of about 40 watts at medium speed is typical. Attic power ventilators energy consumption while the specifics will change with each home the general consensus is that attic power fans actually use more energy than they save. When set at low speed fans use between 15 and 30 watts and at high speed they consume between 50 and 100 watts. Attic ventilation will usually need to be increased to exhaust the fan s air outdoors.

The attic fan kept my house cooler by 8f compared to pre fan installation days. Temp 84f at 5pm.