Where do I connect the pressure switch?

The pressure switch is connected using a three-core cable located on the top of the airhandling unit. Look for a black cable with three conductors. The green and white conductors are used for this function. When contact is established between the green and white wires, the unit will automatically increase the supply air flow. The third conductor is normally not used in this connection. If you are an end user and not comfortable performing the connection yourself, we recommend contacting the service company that installed the system or the retailer where the product was purchased.