Since it is a genuine Lennox part

Is the VG1845FS suitable for steam applications

ensuring exact physical and electrical specs

the ESP200 solid-state design is self-powered from the main circuit

Resideo R845A1030 Relay 320734-701 Since it is a genuineThe Resideo R845A1030 functions as a mission critical hydronic switching relay designed for demanding multi zone boiler applications. This DPST switching relay features an integral transformer providing 24Vac current to power two wire or three wire thermostats, including modern Smart Thermostats with C wire requirements. The double pole single throw configuration allows for simultaneous control of a line voltage circulator pump and a low voltage