Recently we have had calls of an attic fan running in March. The unit was installed one year prior.

The owner wanted the thermostat adjusted for the present time. We suggested shutting off the service switch until the outside temperature exceeded the inside temperature.

Keep in mind that attic fans are installed to exhaust heat from the attic space.

In March, the house is still being heated from the heating system warming the attic.

When we have a warm sunny day in March, the attic heats with both the interior heating system and the sun, which raises the temperature in the attic, causing the fan to run in lower exterior temperatures because the attic is hot.

We recommend shutting the service switch off until May when the attic will be heated from the exterior sources only. (without the interior heating system.)