Heat Controller R68DF0012 Relay 319848-301 cast iron variable pitch sheave

cast iron variable pitch sheave engineered for precise air handling and fan speed adjustments in commercial HVACR systems

Can I use this on 3/8-inch tubing

the 159S uses snap acting switches designed to replace older mercury-style controllers in high-pressure applications up to 150 psi

It also replaces Beckett part numbers 5929 and 5929U

Mechanical fitment is compatible

Heat Controller R68DF0012 Relay 319848-301 cast iron variable pitch sheaveThe Heat Controller R68DF0012 is a professional grade Blower Time Delay Relay engineered to manage precise fan cycling in residential and commercial HVAC systems. Designed for technicians who need a reliable solution for residual heat recovery, this OEM part delays the blower motor's shutdown after the heating or cooling cycle ends. This technical integration ensures that all remaining conditioned air is distributed through the ductwork, maximizing