the 4L420 is a staple for technicians looking to optimize the efficiency of light-duty power transmission while minimizing wear on pulleys and aligned sheaves

provided the temperature and pressure remain within the 240°F and 150 PSI limits

Reliable 120V primary safety control for oil burners

The temperature sensing element must be purchased separately based on your specific resistance requirements

For accurate outside air temperature readings

Belimo B311+LF24-SR Valve Assembly 328140-751 the 4L420 is a stapleThe Belimo B311+LF24 SR is a precision engineered 3 way characterized control valve (CCV) assembly designed for modulating control in closed loop hydronic systems. Featuring a 1 2 inch NPT connection and a 1. 9 Cv rating, this valve utilizes a stainless steel ball and stem to prevent corrosion and ensure long term reliability in demanding HVAC applications. The assembly is paired with the LF24 SR spring return actuator, providing 35 in lb of torque