Fujitsu FO2416RTJNAA - Page 34

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7.0 COMPONENTS & CONTROLS
7.10 Thermal Expansion Valve (TXV)
While scroll compressors usually do not require
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heater should be added. Refrigerant migration
during the off cycle can result in a noisy start up.
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migration, and to help eliminate any start up noise
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is recommended if the system charge exceeds
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bottom of the compressor shell. Its purpose is
to drive refrigerant from the compressor shell
during long cycles, thus preventing damage to the
compressor during start-up.
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least 12 hours before the compressor is started.
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7.11 Compressor Crankcase Heater (CCH)
Components
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valve that opens in the cooling mode to provide
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to help eliminate “hammering” in the off cycle that
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on both the indoor coil and outdoor heat pump unit.
MAXIMUM SYSTEM CHARGE VALUES
Charge Limit
Model Compressor Without
Size Model Number Crankcase Heater*
24
36
48
60
ZPS21K5E-PFV
ZPS30K5E-PFV
ZPS40K5E-PFV
ZPS49K5E-PFV
*9.6 lbs. [4.35 kg]
*9.6 lbs. [4.35 kg]
*12 lbs. [5.44 kg]
*12 lbs. [5.44 kg]
*Crankcase heater factory installed.
7.12 High- and Low-Pressure Controls
7.13 Compressor Hard Start Components
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compressor from operating in pressure ranges
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The high-pressure control (HPC) is an automatic-
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CAUTION: The compressor has an
internal overload protector. Under some conditions,
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condemning the compressor.
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the scroll compressors used in heat pumps, but
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components are desirable to reduce light dimming.
Hard start components must be field installed and
are available through Rheem Parts or Ruud Parts.