The UC1 is the new standard interlock control for Tjernlund's full line of Fixed Speed Power Venters, Draft Inducers and Combustion Air In-Forcers. It can be interlocked with virtually any burner control circuit. Features include: adjustable pre & post purge, LED status / diagnostic indicators, 10 second prover switch delay to avoid burner start up and wind induced short cycling. Interlocks with any 24-120 VAC burner control circuit and also includes ''dry'' contact actuation option. Selectable voltage eliminates false activation by burner control circuits. After each burner cycle the UC1 will continue to operate in post-purge mode to allow the venter to purge the heater and vent of residual flue gases. A factory post-purge time is set at 2 minutes and is adjustable up to 16 minutes.