Now that the thermostat is finally reading 75 degrees +, most of you will be starting your air conditioners for the first time. Before you flip the circuit breaker to bring on the system, be sure your furnace filter is clean and the bypass damper in your humidifier is closed or in the “summer” position.
Your furnace fan runs at a much higher speed (CFM) when your air conditioner is on versus when your furnace is heating, so a clean filter is even more important in the summer.