1.) Use a pressure switch or sail switch located in the main return air duct. In this way,
anytime the HVAC fan is running the 600HS unit will run.
2.) Use the lighted on/off switch to control unit. You can run the unit anytime or all the time
using this approach. The 600HS units are designed to run 24/7.
We recommend you run your HVAC fan all of the time. This will enable you to circulate the
air constantly through the house and air filtration system. This will also help maintain a more
constant temperature throughout the living space.