Who shouldn’t use the whole house fan?
If you suffer from allergies, it might not be a good idea to bring all the pollution into the house. The window screens will stop some of it, but whole house fans are very powerful and will make you sneeze more than ever. Physics of the whole house fan operation! 1. Before you turn the fan on, open as many windows and doors as possible, close fireplace damper and / or glass door, and shut the furnace / water heater room doors (if they are louver type, it won’t matter). The suction of the whole house fan (at least at the highest speed) is so great, that without open windows / doors, it will draw air from the outside through any possible openings like, for example, from the chimney. If it is a fireplace chimney and you don’t remove the ashes… well, it’s going to be a mess. If it is a water heater / furnace chimney, it might blow off the pilots. 2. When everything is ready, you can turn on the whole house fan and usually within the next few seconds you should feel plenty of exterior air f
