Lennox TSA036H4N41 Installation Instructions Manual page 16

START: Determine how refrigerant is metered
WHEN TO CHARGE?
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Warm weather best
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Can charge in colder weather
CHARGE METHOD? Determine by:
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Metering device type
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Outdoor ambient temperature
REQUIREMENTS:
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Sufficient heat load in structure
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Indoor temperature between 70-80ºF (21−26ºC)
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Manifold gauge set connected to unit
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Thermometers:
− to measure outdoor ambient temperature
− to measure liquid line temperature
− to measure suction line temperature
START: Measure outdoor ambient temperature
USE EITHER APPROACH
OR SUBCOOLING
METHOD
WEIGH IN TXV
Refrigerant Charge per Line Set Length
Ounces per 5 feet (g per 1.5 m)
Liquid Line
adjust from 15 feet (4.6 m) line set*
Set Diameter
3/8" (9.5 mm)
3 ounce per 5' (85 g per 1.5 m)
NOTE − *If line length is greater than 15 ft. (4.6 m), add this
amount. If line length is less than 15 ft. (4.6 m), subtract this
amount.
506083−01 03/08
Figure 28. Determining Charge Method
64ºF and
ABOVE or
BELOW
65ºF
and
ABOVE
Figure 29. Weigh In Method
Page 16
TXV
OUTDOOR AMBIENT
TEMPERATURE
65ºF (18.3ºC)
and ABOVE
APPROACH OR
SUBCOOLING
1. Check Liquid and suction line pressures
2. Compare unit pressures with Table 27,
Normal Operating Pressures.
BELOW
3. Conduct
previously outlined.
4. Weigh in the unit nameplate charge plus
any charge required for line set differences
over feet.
64ºF (17.7ºC)
and BELOW
WEIGH-IN
leak check; evacuate
This nameplate is for illustration purposes
only. Go to actual nameplate on outdoor
unit for charge information.
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