27
5.4 Refrigerant Charging
T
he re
frigerant charge for all systems should be
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the access panel cover.
WARNING:
The top of the scroll
compressor shell is hot. Touching the compressor
top may result in serious personal injury.
CAUTION:
R-410A pressures are
approximately 60% higher (1.6 times) than R-22
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refrigerant. Failure to exercise care may result in
equipment damage or personal injury.
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the Charging Chart inside the access panel cover.
IMPORTANT:
Do not operate the
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(liquid and discharge).
NOTICE:
System maintenance is to be
performed by a qualified and certified technician.
The optimum refrigerant charge for any outdoor
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affected by the application. Therefore, charging
data has been developed to assist the field
technician in optimizing the charge for all mounting
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LH – Left-Hand Discharge, and RH – Right-Hand
Discharge). Refer to the charging chart inside the
access panel cover on the unit and choose the
appropriate column for the specific application
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utilizing either an RCF indoor coil installed on a
gas furnace or an (-)H series air handler in the
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require removal of refrigerant since the factory
charge could result in an overcharge condition.
IMPORTANT:
Refrigerant charging
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the 2nd stage mode.
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in the cooling and heating mode. All steps listed
should be performed to ensure proper charge has
been set. For measuring pressures, the service
valve port on the liquid valve (small valve) and the
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valves are to be used.
5.4.1 Measurement Device
Set-Up
1. With an R-410A gauge set, attach the high-
pressure hose to the access fitting on the liquid
line (small) service valve at the OD unit.
2.
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VXFWLRQSRUWORFDWHGEHWZHHQWKHWZRVHUYLFH
valves that is connected to the suction tube
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.
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of the outside of the unit on the copper liquid line
(small line). For more accurate measurements,
clean the copper line prior to measurement and
use a calibrated clamp-on temperature probe or
an insulated surface thermocouple.
5.4.2 Preliminary Charging by
Weight
NOTICE:
Adjust the system charge by
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connecting tubing and indoor coil is adequate;
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Data” in Section 3.3 of
these instructions or on the
unit data plate. Note that the charge value includes
charge required for 15 ft. [4.6 m] of standard-size
liquid line without a filter drier.
Calculate actual charge required with the actual
installed liquid line size and length using:
1/4" [6.4 mm] O.D. = .3 oz./ft. [28.3 g/m]
5/16" [7.9 mm] O.D. = .4 oz./ft. [37.7 g/m]
3/8" [9.5 mm] O.D. = .6 oz./ft. [56.7 g/m]
1/2" [12.7 mm] O.D. = 1.2 oz./ft. [113.3 g/m]
Add 6 oz. for field-installed filter drier.
Charge Adjustment = (Line Set (oz./ft.) × Total
Linear Length) – Factory Charge for Line Set +
6 oz. (for field installed filter drier)
Example:
A three-ton heat pump unit requires 75
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Factory Charge for Line Set
= 15 ft. × .6 oz. = 9 oz.
5.0 SYSTEM START-UP & REFRIGERANT CHARGING
Charging
