Lochinvar & A.O. Smith 100208413 Pump 319848-301 the GC Valves S21 series

the GC Valves S21 series allows for coil replacement or voltage changeouts without disconnecting the valve body from the NPT piping

On the controller end

but includes an LP gas conversion kit to handle propane applications

Using a calibrated manifold gauge and a multimeter

This motor is the standard replacement for Johnson Controls A-4300 and A-4400 series refrigerated air dryers

Lochinvar & A.O. Smith 100208413 Pump 319848-301 the GC Valves S21 seriesThe Lochinvar & A. O. Smith 100208413 Pump is a critical bypass loop pump engineered for high demand hydronic heating and domestic hot water applications. Designed to maintain precise thermal equilibrium, this OEM circulation pump prevents uneven heat distribution and localized "hot patches" by ensuring continuous fluid movement through the secondary loop. This constant circulation protects the heat exchanger from thermal stress and stagnation,