For 1" 800M4 assemblies

the contacts should be open

This model uses a 3/4 inch NPT (National Pipe Thread) fitting

Check for dirty air filters

York S1-024-19082-740 Sequencer Relay Els PW 17895 For 1" 800M4 assembliesThe York S1 024 19082 740 Sequencer Relay is a heavy duty, field proven 24V heat sequencer relay designed to manage stage activation in electric furnaces and air handlers. Utilizing a solid state positive temperature coefficient (PTC) heater and bimetallic discs, this control ensures precise, staggered firing of heating elements to prevent high inrush currents and potential circuit breaker trips. It functions by converting a low voltage signal from