Used for side wall venting commercial natural gas or LP fired equipment including: boilers, water heaters and unit heaters. All models feature the new UC1 universal control and a diaphragm fan proving switch safety interlock which will shut down heating equipment if a venting malfunction occurs. UC1 universal control features include, adjustable pre and post-purge settings, LED status/diagnostic indicators, fan prover switch monitoring. Interlocks with any 24 - 120 VAC burner control circuit and also includes dry contact actuation option. Easily interlock multiple appliances with our MAC-series multiple appliance controls. Allows for a significant reduction in vent pipe diameter to save on costly materials and labor. Built-in adjustable damper also allows regulation for maximum combustion efficiency.