A line of Auto-Draft® RT Series rooftop inducers have a constant operating pressure (COP) control. The COP control delivers precise draft or exhaust by modulating fan speed to deliver a constant negative pressure within a chimney or chase as draft requirements or exhaust loads change. According to the manufacturer, the result is common vented boilers, water heaters, and clothes dryers operate more efficiently, while rooftop chase exhaust fans modulate to actual demand, saving make-up air and motor power consumption. Rooftop inducers with onboard draft COP controls and burner interlocks are designed for noncondensing modulating gas- and oil-fired heaters and multiple heaters tied into a common vent. The COP controller has soft start and soft transition between speeds, which translates into quick and extremely smooth reaction to firing rate changes. RT Series inducers and COP controllers are ETL-listed and available in two capacity ranges — RT750 models from 250 to 750 cfm and RT1500 from 750 to 1,500 cfm. The inducers can be mounted on tile-lined chimneys or metal flues/vents. During inspection or chimney cleaning, the fan assembly can be tilted away from the base plate for maximum accessibility to the chimney or vent pipe interior.
Tjernlund Products Inc.