Brochure

Catalog CIC-2003-1/US
Refrigeration Solenoid Valves
Parker Hannifin Corporation
Climate & Industrial Controls Group
Cleveland, OH
259
Refrigeration
Solenoid Valves
Model CS & DS
Pulse Width Modulating Valves
Parker’s pulse width solenoid valves are designed to
meter the refrigerant flow of mechanical refrigeration
systems.
The pulse width solenoid valve, (PWM) when
interfaced with microcomputers and appropriate
sensors, precisely meters the refrigerant flow to
control superheat evaporator pressure and other
system parameters including the implementation of
diagnostic functions (i.e.-charge level, crankcase
temperature, oil pressure, current draw, values of
high and low side pressures and temperatures).
Using a modified solenoid valve construction
coupled with technology developed within Parker
Hannifin, life cycles in excess of 100 million cycles
are attainable. The PVM valve is well suited for
systems employing variable speed compressor
technology where pulse frequencies as low as 5 HZ
may be used.
Unlike conventional thermostatic expansion valves,
the PWM valve does not depend on refrigerant,
system pressures or temperatures. In addition, the
valve does not require a charged power element,
capillary lines or external equalizer. Compared to
conventional thermostatic expansion valves, the
PWM valves do not require superheat change with
load variations. The Parker PWM valve provides
stable system control and constant superheat
throughout load variations and discharge pressures.
The system superheat can be held constant or
changed to meet varying operational parameters
such as compressor overload. Additionally, various
methods of anticipating error through superheat
change can be used to eliminate the refrigerant flow
from over and under feed which causes hunting.
Features
• Long Life (100 million cycles).
• Suitable for all common refrigerants except
ammonia.
• Maximum use of entire evaporator surface with
minimum superheat result in increased efficiency
(SEER).
• No superheat adjustment necessary.
• Wide range capacity results in reduced inventory.
• Fast, precise response to load changes.
• Readily adaptable to providing functions related to
Maximum Operating Pressure (M.O.P.).
• Remote system control.
• Readily interfaces with a microcomputer and variable
speed capacity compressor technology.
• Standard angle pattern solder connections–
3/8 ODM x 3/8 ODM (Model HP)
3/8 ODM x 1/2 ODF (Models CS/DS)
(Consult Parker for different connections.)
• U.L. Recognized– File MH5567.
Model HP
Technical Information Pulse Width Modulating Valves