You must check the serial plate of the wall-mount unit to ensure the 10kW kit is listed as an approved accessory for that specific model and cabinet size

and MR/MS series modules

check the relay coil resistance between terminals 2 and 5

If the system pressure is within 10% of the 80 PSI set pressure

Is the light green housing color significant

Schneider Electric (Barber Colman) 2390-501 Gradual Switch Freon You must check the serialThe Schneider Electric 2390 501 Gradual Switch is a precision engineered pneumatic manual positioner designed for proportional control in commercial HVACR systems. Utilizing a reliable manual dial, this device allows technicians to modulate output pressure from 0 to 20 psig, providing direct control over pneumatic actuators, dampers, and valves. Built for durability and accuracy, the 2390 501 operates with a 20 psig main air pressure and delivers an 8