System Operation; Maintenance - Lennox 10ACC-018 User Manual

Normal Operating Pressures In psig (liquid and vapor +/− 2 psig)*
Out. Coil
Unit /
Entering Entering
Metering Metering
Air Temp.
Device
LIQ.
5F (5C)
65 (18.3) 153
75 (23.9) 180
85 (29.4) 209
10ACC / 10ACC /
95 (35.0) 240
TXV TXV
105 (40.6) 274
110 (43) 292
115 (45) 311
65 (18.3) 155
75 (23.9) 182
85 (29.4) 211
10ACC /
95 (35.0) 242
fixed orifice fixed orifice
105 (40.6) 274
110 (43) 291
115 (45) 308
*These are typical pressures only. Indoor indoor match up, indoor air quality, and indoor load will cause the pressures to vary.

System Operation

The outdoor unit and indoor blower cycle on demand from
the room thermostat. When the thermostat blower switch is
in the ON position, the indoor blower operates continuously.

Maintenance

Maintenance and service must be performed by a qualified
installer or service agency. At the beginning of each cooling
season, the system should be checked as follows:
WARNING
Electric shock hazard. Can cause inju-
ry or death. Before attempting to per-
form any service or maintenance, turn
the electrical power to unit OFF at dis-
connect switch(es). Unit may have
multiple power supplies.
1 − Clean and inspect the outdoor coil. The coil may be
flushed with a water hose. Make sure power is off be-
fore cleaning.
2 − Condenser fan motor is prelubricated and sealed. No
further lubrication is needed.
3 − Visually inspect connecting lines and coils for evidence
of oil leaks.
4 − Check wiring for loose connections.
−018 −024
SUC. LIQ. SUC. LIQ.
71 163 70 175
72 193 71 206
73 225 72 241
77 260 73 277
79 298 74 316
80 318 75 336
81 338 75 357
62 165 63 181
68 194 67 211
72 224 70 242
77 257 73 276
80 293 76 313
81 313 78 332
83 332 79 353
Table 7
−030 −036
SUC. LIQ. SUC. LIQ.
76 162 70 173
77 187 74 201
78 219 75 234
80 253 77 269
81 291 79 307
82 310 80 326
83 329 81 346
69 168 67 178
73 195 71 202
76 224 75 235
79 255 78 270
81 289 82 308
82 305 83 326
84 324 84 347
5 − Check for correct voltage at unit (unit operating).
6 − Check amp−draw condenser fan motor.
Unit nameplate _________ Actual ____________ .
NOTE − If the owner complains of insufficient cooling,
the unit should be gauged and the refrigerant charge
should be checked. Refer to the charging section in
this instruction.
Indoor Coil
1 − Clean coil, if necessary.
2 − Check connecting lines and coils for evidence of oil
leaks.
3 − Check the condensate pan line and clean it if necessary.
Indoor Unit
1 − Clean or change filters.
2 − Adjust blower speed for cooling. Measure the pressure
drop over the coil to determine the correct blower CFM.
Refer to the unit information service manual for pressure
drop tables and procedure.
3 − Belt Drive Blowers − Check belt for wear and proper
tension.
4 − Check all wiring for loose connections
5 − Check for correct voltage at unit (blower operating).
6 − Check amp−draw on blower motor
Unit nameplate_________ Actual ____________.
Page 15
−042 −048
SUC. LIQ. SUC. LIQ.
73 159 71 170
74 188 72 201
74 220 73 234
75 251 76 270
76 290 77 309
77 309 78 331
78 328 79 351
67 163 68 189
70 190 71 203
71 220 74 233
74 251 77 265
78 288 79 301
79 307 80 319
80 325 82 339
−060
SUC.
74
76
77
79
79
80
81
72
74
77
79
82
83
84