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Section 9:
Refrigeration Circuits and Piping:
WARNING
EXPLOSION HAZARD
System contains R-410A
refrigerant. Operating pressures
may exceed limits of R-22 service
equipment. Use proper refrigerant
handling practices, tools, and
equipment. Failure to follow these
instructions can result in death,
injury, or property damage.
CAUTION
PRODUCT DAMAGE HAZARD
System contains R-410A
refrigerant. Operating pressures
may exceed limits of R-22 service
equipment. Use only R-410A
refrigerant and POE 3MAF
compressor oil. Failure to follow
these instructions can result in
equipment damage.
9.1 Refrigerant
This unit utilizes R-410A, a refrigerant with a zero ozone
depletion rating, and POE (Copeland) or PVE (Bitzer)
refrigerant oil. Equipment utilizing R-410A refrigerant
operates at higher pressures than other typical
refrigerants. System components have been sized and
pressure switch settings have been adjusted for the
system refrigerant flows and higher operating pressures.
The unit has a broad application range. For optimum
performance and efficiency, it may be necessary to adjust
the refrigerant charge to maintain desired subcooling and
superheat at operating temperature extremes.
9.2 Components and Configurations
There are many different refrigeration circuit variations
available. Depending on the configuration, the unit may
include, but is not limited to, the following components:
• Accumulator
• Coil
• Evaporator coil
• Condenser coil
• Coaxial coil
• Compressor
• Standard scroll
• Variable Speed Scroll
• Digital scroll
• Filter drier
• Hot gas bypass valve
• Hot gas reheat components
• Check valve
• Coil
• Solenoid valve (standard) or modulating bypass/
reheat valves (modulating)
• Oil separator
• Receiver
• Refrigerant pressure switches- high and low
• Non-adjustable
• Switchable liquid sub-cooling components
• Coil
• Two solenoid valves
• Check valve
• Thermal expansion valve (TXV)
See Figure 7 through Figure 11 for schematics of the
most common refrigeration circuit configurations. All
schematics illustrate a single-compressor, single-circuit,
cooling-only system.
• For single-circuit systems with a tandem
compressor, the pair of compressors are mounted on
a common base that are used together on a single
refrigeration circuit.
• For dual-circuit systems with two independent
compressors, the circuitry and components are
duplicated for the second circuit.
• For heat-pump systems, a reversing valve is included.
PR Series Installation, Operation, and Maintenance Manual
