Specifications

9
CAPACITY CONTROL SYSTEM
Capacity Control Electric – Electrically operated control valve is actuated by remote signal to the electric solenoid coil, which has
the same voltage as the unit control voltage, No manual adjustments to the electric unloaded valve are necessary. When the solenoid
is "de-energized", the passageways in the valve are aligned for "loaded" Conditions. When the solenoid is " energized" the valve
passageways are aligned for unloading.
LOADED OPERATION
This capacity control valve is controlled by an electric solenoid. When the solenoid is de-energized, the valve loads the cylinder
bank (2 cylinders) as show in the above figure.
When the suction pressure rises above a set point, an external controller de-energizes the solenoid coil. This closes the capacity
control valve port, allowing discharge pressure to build-up behind the unloaded piston assembly. A high enough pressure will
compress the unloaded valve spring, opening the unloaded suction port. Suction gas can now be drawn into the cylinders, running the
bank fully loaded.
UNLOADED OPERATION
As the suction pressure drops below the set point of an external controller, the solenoid coil is energized. This opens the capacity
control valve port, allowing the discharge gas behind the unloaded piston assembly to vent back to the suction side. The unloaded
valve spring at this point can move the unloaded valve body to the left, blocking the unloaded suction port. The cylinder bank is now
isolated from the compressor suction manifold, unloading these two cylinders. No refrigerant is allowed into the cylinders and no
compression takes place.
Operation for plc seires For learning how to work with controller see manual catalogue.