Johnson Controls A-4000-138 Station Refrigerant this specific thermostatic expansion valve

this specific thermostatic expansion valve is calibrated for the pressure-temperature characteristics of R-22 and should not be used in R-410A applications

OEM Performance: Ensures exact electrical matching with Raypak heater parts

What causes a humming or chattering noise during operation

and check the 80V HSI for continuity

Johnson Controls A-4000-138 Station Refrigerant this specific thermostatic expansion valveThe Johnson Controls A 4000 138 is a professional grade remote mounted pressure reducing station engineered to maintain precise pneumatic control system performance. This unit effectively regulates output pressure within a tight 0. 02 psi tolerance, even when managing input pressure variations of up to 20 psi. Designed for rigorous HVACR environments, it handles a maximum input pressure limit of 300 psig and provides a reliable air flow capacity of 25