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Water side heat exchanger
RTXC XE uses a falling film evaporator to exchange heat of refrigerant in the shell side with water flow in
tubes. In cooling mode, liquid refrigerant evenly drop on the external surface of tube bundle and exchange
heat with water flow in tube, specified liquid level in falling film maintained by expansion valve to ensure high
efficiency of the heat exchange, vapored refrigerant exit through the suction line, excessive refrigerant and oil
left at the bottom of falling film through oil return valve back to compressor. In heating mode, the refrigerant
gas discharged by the compressor through the tube bundle to release heat, and the condensed liquid
refrigerant drain from the bottom of the shell.
Electrical heaters embedded in both sides of water box and an electrical heat strip twined on the outside
surface of the shell beneath the insulation to prevent heat exchanger from freeze in the winter. Additional
230V field provided single phase power connection is required to power the heaters.
CAUTION - Equipment Damage!
The electrical heater of water side should be field-suppiled an independent 230V single phase AC
power source.
Economizer (Only for RTXC110/180/220XE)
RTXC XE uses a brazed plate heat exchanger as economizer. A portion of liquid refrigerant through
economizer EXV to vaporize and create the additional sub-cooling to the major liquid refrigerant is injected
into the compressor at a midway point of the compression process. The major of liquid flow cooled down
goes through the main EXV to the evaporator. Therefore enhances cycle capacity and in some cases
improve cycle efficiency by increasing compressor displacement and degree of sub-cooling of the main
refrigerant circuit.
Expansion Valve
RTXC XE main refrigerant loop uses two electrical expansion valves for cooling and heating respectively. In
cooling condition, cooling EXV modulate according to the liquid level of the falling film monitoring by liquid
level sensor. In heating condition, the heating EXV is controlled by regulating the suction superheat of the
compressor. The flow of refrigerant into the economizer branch is alse controlled by the electronic expansion
valve per the superheat of gas injected into compressor. Oil circuit using TXV to maintain the oil temperature
by adjust refrigerant flow rate through oil cooler.
Oil separator
The compressor discharges refrigerant gas to the tangential entrance at the top of oil separator and rotate
along the cylinder, oil droplets throw out from the refrigerant gas by the centrifugal force and fall downward
the cylinder into the oil sump at the bottom, then return back to compressor. The purified refrigerant gas exits
from the top of the oil separator and flow into the condenser through reversing valve.
Fan
In cooling condition, all fans operate in high speed when ambient temperature is high, automatically adjust
fan stage when ambient temperature decreased. In heating condition, all fans run in high speed except
warmup and defrost. The fans are propeller-type and not recommended for use with ductwork, filters or other
impediments to airflow in the fan air stream.
Oil Circuit
The majority of the oil that is mixed with vapored refrigerant discharged from compressor is separated and
recollected at the bottom of the oil separator, minority rest oil enters system with refrigerant discharge gas. The
majority oil in the sump flows through oil cooler, shut off valve, internal filter and oil supply check valve back to
compressor then divides into two ways: one oil flow injects into rotors from top shell of compressor to lubricate
rotors and seal the gaps between rotors and house, another oil flow injects into the bearing chamber to lubricate
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