Slide Valve Movement; Oil Management System; Oil Separator - Trane AdaptiR RTHD Installation Operation & Maintenance

Slide Valve Movement

Movement of the slide valve piston
regulates compressor capacity. Compressed vapor flowing in to and out of the cylinder governs
piston movement, and is controlled by the load and unload solenoid valves.
The solenoid valves (both normally closed) receive "load" and "unload" signals from the Sym-
bio800, based on system cooling requirements. To load the compressor, the Symbio800 opens
the load solenoid valve. The pressurized vapor flow then enters the cylinder and, with the help of
the lower suction pressure acting on the face of the unloader valve, moves the slide valve over
the rotors toward the suction end of the compressor.
The compressor is unloaded when the unload solenoid valve is open. Vapor "trapped" within the
cylinder is drawn out into the lower-pressure suction area of the compressor. As the pressurized
vapor leaves the cylinder, the slide valve slowly moves away from the rotors toward the dis-
charge end of the rotors.
When both solenoid valves are closed, the present position of slide valve is maintained.
On compressor shutdown, the unload solenoid valve is energized. Springs assist in moving the
slide valve to the fully-unloaded position, so the unit always starts fully unloaded. The slide valve
moving principle of RTHD variable volume ratio compressor is same with traditional RTHD com-
pressor, the spring is removed for RTHD variable volume ratio compressor.

Oil Management System

Oil Separator

The oil separator consists of a vertical cylinder surrounding an exit passageway. Once oil is in-
jected into the compressor rotors, it mixes with compressed refrigerant vapor and is discharged
directly into the oil separator. As the refrigerant-and-oil mixture is discharged into the oil separa-
tor, the oil is forced outward by centrifugal force, collects on the walls of the cylinder and drains
to the bottom of the oil separator cylinder. The accumulated oil then drains out of the cylinder
and collects in the oil sump located near the top and in-between the evaporator and condenser
shells.
Oil that collects in the oil tank sump is at condensing pressure during compressor operation;
therefore, oil is constantly moving to lower pressure areas.
RTHD-SVX04K-EN
Operating Principles Mechanical
(Figure 35) determines slide valve position which, in turn,
83