Lennox SSB*H4 Manual page 16

5 − Compare the subcooling value with those in table 6. If
subcooling is greater than shown, recover some refrig-
erant. If subcooling is less than shown, add some refrig-
erant. Be aware of the R−410A refrigerant cylinder. It will
be light maroon−colored. Refrigerant should be added
through the vapor line valve in the liquid state.
TABLE 5
R−410A Temperature (°F) − Pressure (Psig)
°F Psig °F Psig
32 100.8 64 181.6
34 105.0 66 187.7
36 109.2 68 194.1
38 113.6 70 200.6
40 118.0 72 207.2
42 122.6 74 214.0
44 127.3 76 220.9
46 132.2 78 228.0
48 137.1 80 235.3
50 142.2 82 242.7
52 147.4 84 250.3
54 152.8 86 258.0
56 158.2 88 266.0
58 163.9 90 274.1
60 169.6 92 282.3
62 195.5 94 290.8
TABLE 6
SSB*H4 Subcooling Values for Charging
Second Stage (High-Capacity)
_ Saturation Temperature
_ Liquid Line Temperature
_ Subcooling Value
=
Model SPB036H4S41
°F (°C)* 6 (3.3)
*F: +/−1.0°; C: +/−0.5°
Charge Using the Approach Method, TXV Systems
Outdoor Temperature > 65ºF (18ºC)
Use the same digital thermometer to check the outdoor
ambient temperature and the liquid line temperature.
The following procedure is intended as a general guide and is
for use on expansion valve systems only. For best results, in-
door temperature should be 70°F (21°C) to 80°F (26°C).
Monitor system pressures while charging.
1 − Record outdoor ambient temperature using a digital
thermometer.
2 − Attach high pressure gauge set and operate unit for sev-
eral minutes to allow system pressures to stabilize.
3 − Compare stabilized pressures with those provided in
table 8, Normal Operating Pressures." Pressures high-
er than those listed indicate that the system is over-
charged. Pressures lower than those listed indicate that
the system is undercharged. A temperature/pressure
chart for R−410A refrigerant is provided in table 5 for
your convenience. Verify adjusted charge using the ap-
proach method.
°F Psig °F Psig
96 299.4 126 451.8
98 308.2 128 463.5
100 317.2 130 475.6
102 326.4 132 487.8
104 335.7 134 500.2
106 345.3 136 512.9
108 355.0 138 525.8
110 365.0 140 539.0
112 375.1 142 552.3
114 385.4 144 565.9
116 396.0 146 579.8
118 406.7 148 593.8
120 417.7 150 608.1
122 428.8 152 622.7
124 440.2 154 637.5
126 451.8 156 652.4
SPB048H4S41 SPB060H4S41
6 (3.3) 9 (5.0)
4 − The difference between the ambient and liquid tempera-
tures should match values given in table 7. If the values
don't agree with the those in table 7, add refrigerant to
lower the approach temperature, or recover refrigerant
from the system to increase the approach temperature.
Be aware of the R−410A refrigerant cylinder. It will be
light maroon−colored. Refrigerant should be added
through the vapor valve in the liquid state.
SSB*H4 Approach Values for Charging (Second
_ Liquid Line Temperature
_ Outdoor Temperature
_ Approach Temperature
=
Model SSB036H4S41
°F (°C)* 10 (5.6)
*F: +/−1.0°; C: +/−0.5°
IMPORTANT
Table 8 is not a procedure for charging the system but
may be used to perform maintenance checks. Minor
variations in these pressures may be due to differ-
ences in installations. Significant deviations could
mean that the system is not properly charged or that
a problem exists with some component in the system.
Normal Operating Pressures In psig
(liquid +/− 10 and vapor+/− 5 PSIG)*
Temp. of
SSB036H4S41
air enter- air enter-
ing out-
door coil
5F (5C)
Liquid
First Stage (Low Capacity)
65 (18.3) 227
75 (23.9) 261
85 (29.4) 302
95 (35.0) 347
105 (40.6) 396
115 (46.1) 452
Second Stage (High Capacity)
65 (18.3) 244
75 (23.9) 278
85 (29.4) 321
95 (35.0) 368
105 (40.6) 419
115 (46.1) 476
*These are typical pressures only. Indoor indoor match up, in-
door air quality, and indoor load will cause the pressures to vary.
Page 16
TABLE 7
Stage)
SSB048H4S41 SSB060H4S41
8 (4.4) 3 (1.7)
TABLE 8
SSB048H4S41 SSB060H4S41
Suc- Suc-
tion tion
Liquid Liquid
137 224 142 215
142 258 144 250
145 299 146 291
147 345 148 337
150 395 150 388
154 450 153 444
132 235 135 220
139 269 137 256
142 313 139 299
144 361 141 347
147 412 143 402
150 471 146 462
Suc-
tion
136
139
142
144
146
148
130
133
136
138
141
143