36
Receiver
Figure 16 RTXC XE Single Refrigerant Circuit
(Economizer Only for RTXC110/180/220XE)
Refrigerant
NOTICE - Equipment damage!
Use only refrigerants specified on the unit nameplate and Trane OIL00317.
Failure to do so may cause compressor damage and improper unit operation.
Compressor
The compressor is of cast iron, semi-hermetic construction, twin screw type. Each compressor has two rotors
- “male” and “female” - which provide compression. The male rotor is attached to, and driven by, the motor,
and the female rotor is, in turn, driven by the male rotor. Separately housed bearing sets are provided at each
end of both rotors. A two-pole, hermetic, induction motor (3000 rpm at 50 Hz, 3600 rpm at 60 Hz) drives the
compressor rotors. The motor is cooled by suction refrigerant gas, entering the end of the motor housing
through the suction line.
The female side port represents a first capacity step from 30% to approximately 60%. The slide piston
uncovers a series of radial ports in the top of the male rotor bore area of the housing, providing continuously
variable unloading from 60% to approximately 100% of compressor suction flange volume flow rate.
Economizers can be used with the compressor to increase cycle capacity and in some cases improve cycle
efficiency, depending on the port machined into the rotor housing for economizer gas injection. The
economizer should only be modulated once the compressor is running at 100% load and closed before the
compressor shut down.
Oil Filter
Each compressor is equipped with a replaceable element oil filter. The filter removes any impurities that
could foul the solenoid valve orifices and compressor internal oil supply galleries.
Air side heat exchanger
Air-cooled heat exchangers are wavy aluminum fins mechanically bonded to internal-finned copper tubing
and factory proof and leak tested. Direct-drive axial discharge fans are balanced and individually protected.
Three-phase fan motors with permanently lubricated ball bearings and external thermal protection are
provided. Units will start and operate at ambient range from 32
o
F (0
o
C) to 114.8
o
F (46
o
C) in cooling mode,
and from 14
o
F (-10
o
C) to 70
o
F (21
o
C) in heating mode.
