Section V: Installations Requiring An Add-On Txv Kit; Section Vi: Evacuation; Section Vii: System Charge; Saturated Properties - Johnson Controls 13 SEER Installation Manual

SECTION V: INSTALLATIONS REQUIRING
AN ADD-ON TXV KIT
For installations requiring a TXV kit, refer to the Installation Instructions
accompanying the TXV kit.
Schrader valve core MUST NOT be installed with TXV installation.
Poor system performance or system failure could result.

SECTION VI: EVACUATION

It will be necessary to evacuate the system to 500 microns or less. If a
leak is suspected, leak test with dry nitrogen to locate the leak. Repair
the leak and test again.
To verify that the system has no leaks, simply close the valve to the vac-
uum pump suction to isolate the pump and hold the system under vac-
uum. Watch the micron gauge for a few minutes. If the micron gauge
indicates a steady and continuous rise, it's an indication of a leak. If the
gauge shows a rise, then levels off after a few minutes and remains
fairly constant, it's an indication that the system is leak free but still con-
tains moisture and may require further evacuation if the reading is
above 500 microns.

SECTION VII: SYSTEM CHARGE

The factory charge in the outdoor unit includes enough charge for the
unit, a 15 ft. line set, and the smallest indoor coil match-up. Some
indoor coil matches may require additional charge. See tabular data
sheet provided in unit literature packet for charge requirements.
Do not leave the system open to the atmosphere.
The "TOTAL SYSTEM CHARGE" must be permanently stamped on the
unit data plate.
Total system charge is determined as follows:
1. Determine outdoor unit charge from tabular data sheet.
2. Determine indoor coil adjustment from tabular data sheet.
3. Calculate the line charge using the tabular data sheet if line length
is greater than 15 feet.
4. Total system charge = item 1 + item 2 + item 3.
5. Permanently stamp the unit data plate with the total amount of
refrigerant in the system.
Use the following charging method whenever additional refrigerant is
required for the system charge.
TABLE 2: R-22 Saturated Properties
Pressure Pressure
Temp °F
PSIG PSIG
80 48 110
82 49 112
84 50 114
86 51 116
88 52 118
90 54 120
92 55 122
94 56 124
96 57 126
98 58 128
100 59 130
102 60 132
104 61 134
106 62 136
108 63 138
Johnson Controls Unitary Products
Pressure
Temp °F Temp °F
PSIG
64 140 78
65 142 79
66 144 80
67 146 81
68 148 82
69 150 83
70 152 84
71 154 84
72 156 85
73 158 86
74 160 87
75 162 88
76 164 88
77 166 89
78 168 90
Refrigerant charging should only be carried out by a qualified air
conditioning contractor.
Compressor damage will occur if system is improperly charged. On
new system installations, charge system per tabular data sheet for
the matched coil and follow guidelines in this instruction.
If a calibrated charging cylinder or accurate weighing device is avail-
able, add refrigerant accordingly. Otherwise, model-specific charging
charts are provided on the access panel of the unit. If mix matched TXV
indoor coils are used with these models, the following subcooling charg-
ing method must be used. Superheat charging charts are not valid with
TXV equipped systems.
SUBCOOLING CHARGING METHOD - MIXED MATCH
COILS
The recommended subcooling is 10°F
1. Set the system running in the cooling mode by setting the thermo-
stat at least 6°F below the room temperature.
2. Operate the system for a minimum of 15-20 minutes.
3. Refer to the tabular data sheet for the recommended airflow and
verify this indoor airflow (it should be about 400 SCFM per ton).
4. Measure the liquid refrigerant pressure P and temperature T at the
service valve.
5. Calculate the saturated liquid temperature ST from Table 2.
6. Subcooling temperature TC = Saturated Temperature (ST) - Liquid
Temp (T).
Example: The pressure P and temperature T measured at the liq-
uid service port is 196 psig and 90°F, respectlvely. From Table 2,
the saturated temperature for 196 psig is 100°F. The subcooling
temperature TC = 100°-90°=10°F
Add charge if the calculated subcooling temperature TC in Step 6 is
lower than the recommended level. Remove and recover the refrigerant
if the subcooling TC is higher than the recommended level. See Table
2.
Check flare caps on service ports to be sure they are leak tight. DO
NOT OVERTIGHTEN (between 40 and 60 inch - lbs. maximum).
Pressure Pressure
Temp °F
PSIG PSIG
170 91 200
172 91 202
174 92 204
176 93 206
178 94 208
180 94 210
182 95 212
184 96 214
186 97 216
188 97 218
190 98 220
192 99 222
194 99 224
196 100 226
198 101 228
347337-UIM-A-0408
Pressure
Temp °F Temp °F
PSIG
101 230 111
102 232 112
103 234 112
103 236 113
104 238 114
105 240 114
105 242 115
106 244 115
107 246 116
107 248 117
108 250 117
109 252 118
109 254 118
110 256 119
111 258 119
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