This specific model features a factory-set

provided the spring is correctly calibrated for the gas type

this internal pilot-operated valve ensures rapid venting and reliable performance

Common indicators include visible corrosion through the casing

Armstrong Fluid Technology 425742-001 Impeller Washer 321702-401 This specific model features aThe Armstrong Fluid Technology 425742 001 Impeller Washer is a precision engineered HVAC pump component designed for high performance fluid system maintenance. Engineered to meet exact Armstrong pump repair parts specifications, this stainless steel washer ensures optimal axial positioning and stability for the impeller assembly. By maintaining tight tolerances within the pump casing, it prevents excessive vibration and premature wear on the rotating