The SPDT terminals allow for "break on rise" or "make on rise" configurations

or an "Open Pressure Switch" error code on the furnace control board

the H19AA-4 is identical to the H19AA-4C and can be used interchangeably in all applications

Exceptional Air Handling: Naturally purges air and non-condensable gases during start-up

and its heavy-duty construction allows for seamless operation in 250mv to 750mv millivolt heat-only applications

Resideo 40003916-047 Replacement Motor 326058-757 The SPDT terminals allow forThe Resideo 40003916 047 Replacement Motor is a high torque 120Vac zone valve motor engineered specifically for Honeywell V4044A series diverting valves. Designed as a direct fit replacement powerhead, this unit features 96 inch leadwires and a manual lever for system positioning during startup or maintenance. For service technicians, this assembly is the standard solution for restoring hydronic heating system flow control without necessitating the