System Operation - Lennox Elite XC14−018−230 Installation Instructions Manual

Table 4. Normal Operating Pressures (Liquid +10 and Suction +5 psig)
IMPORTANT
Model −018
**Temp.
Liquid /
5F (5C)
Suction
Expansion Valve (TXV)
65 (18) 230 / 138
70 (21) 244 / 139
75 (24) 265 / 140
80 (27) 286 / 140
85 (29) 307 / 142
90 (32) 330 / 143
95 (35) 351 / 144
100 (38) 380 / 144
105 (41) 407 / 145
110 (43) 436 / 146
115 (45) 466 / 147
Fixed Orifice (RFC)
65 (18) 232 / 124
70 (21) 248 / 127
75 (24) 267 / 131
80 (27) 286 / 135
85 (29) 307 / 138
90 (32) 328 / 141
95 (35) 351 / 143
100 (38) 375 / 146
105 (41) 400 / 148
110 (43) 426 / 150
115 (46) 457 / 153
*Values shown are typical pressures; indoor unit match up, indoor air quality equipment, and indoor load will cause the pressures to vary.
**Temperature of the air entering the outside coil.

System Operation

UNIT COMPONENTS
High Pressure Switch (S4)
XC14 units are equipped with a high-pressure switch that
is located in the liquid line of the compressor as illustrated
in Unit Dimensions on page 2. The switch is a Single Pole,
Single Throw (SPST), manual−reset switch with red cap
that is normally closed and removes power from the
compressor when discharge pressure rises above factory
setting at 590 + 10 psi.
Thermal Protection Switch (S5)
Mounted
This unit is equipped with a discharge line mounted
temperature switch that prevents compressor damage
due to loss of charge. The switch is located on the
discharge line (see figure 1 for location). When the switch
senses a discharge line temperature of 220°F +/−5°F, it
opens to shut off compressor operation. The auto−reset
switch closes when the discharge line temperature drops
below 180°F +/−9°F and the compressor is re−energized.
This single−pole, single−throw (SPST) bi−metallic switch is
506636−01
Use this table to perform maintenance checks; it is not a procedure for charging the
system. Minor variations in these pressures may be due to differences in installations.
Significant deviations could mean that the system is not properly charged or that a
problem exists with some component in the system.
−024 −030
Liquid / Liquid /
Suction Suction
225 / 135 226 / 129
242 / 137 241 / 131
260 / 138 259 / 134
282 / 140 281 / 138
304 / 141 301 / 140
326 / 142 324 / 141
351 / 142 348 / 142
376 / 144 372 / 143
403 / 145 399 / 144
433 / 145 428 / 145
463 / 147 456 / 146
228 / 125 229 / 128
244 / 127 243 / 129
261 / 131 261 / 132
284 / 134 284 / 135
303 / 137 305 / 138
325 / 140 327 / 140
347 / 142 349 / 142
370 / 144 372 / 144
394 / 146 396 / 146
420 / 148 422 / 148
447 / 150 449 / 150
Discharge Line
−036 −041
Liquid / Liquid /
Suction Suction
238 / 132 233 / 142
254 / 135 239 / 142
273 / 138 256 / 143
293 / 140 278 / 144
316 / 142 299 / 145
340 / 143 321 / 145
366 / 144 343 / 146
392 / 145 366 / 147
420 / 147 389 / 148
449 / 148 421 / 149
480 / 149 452 / 151
241 / 131 228 / 131
258 / 134 245 / 135
277 / 136 263 / 138
298 / 139 284 / 141
321 / 141 306 / 144
342 / 143 327 / 146
366 / 145 348 / 148
392 / 147 372 / 149
416 / 149 395 / 151
446 / 151 424 /153
480 / 152 453 / 155
wired in series with the 24V Y input signal to control
compressor operation.
Thermal Protection Switch (S173)
Some units are equipped with a compressor mounted
normally closed temperature switch that prevents
compressor damage due to overheating caused by
internal friction. The switch is located on top of the
compressor casing (see figure 1). This switch senses the
compressor casing temperature and opens at 239−257°F
(115°C−125°C) to shut off compressor operation. The
auto−reset switch closes when the compressor casing
temperature falls to 151−187°F (66°C−86°C), and the
compressor is re−energized. This single−pole, single−throw
(SPST) bi−metallic switch is wired in series with the 24V Y
input signal to control compressor operation.
Crankcase Thermostat (S40) (−041, −047, −048 and
Compressor in the above reference units are equipped
with a 70 watt, belly band type crankcase heater. HR1
prevents liquid from accumulating in the compressor. HR1
is controlled by a thermostat located on the liquid line.
Page 28
−042 −047
Liquid / Liquid /
Suction Suction
236 / 138 233 / 139
253 / 140 252 / 140
273 / 141 272 / 141
296 / 142 294 / 142
318 / 143 315 / 142
341 / 144 338 / 144
366 / 146 361 / 144
392 / 147 387 / 144
417 / 148 413 / 145
445 / 149 442 / 148
475 / 151 465 / 148
248 / 135 232 / 125
266 / 138 249 / 129
285 / 141 268 / 133
305 / 143 286 / 136
327 / 145 312 / 140
349 / 147 332 / 142
372 / 149 357 / 144
396 / 150 379 / 146
421 / 152 406 / 149
447 / 153 430 / 150
476 / 154 460 / 152
Mounted
−060 units only)
−048 −060
Liquid / Liquid /
Suction Suction
238 / 136 239 / 133
256 / 138 258 / 135
277 / 139 278 / 136
299 / 140 300 / 137
320 / 139 323 / 138
343 / 140 346 / 139
369 / 141 370 / 140
395 / 142 396 / 142
422 / 144 415 / 143
450 / 146 449 / 145
481 / 148 476 / 147
240 / 126 244 / 125
260 / 129 263 / 128
281 / 133 281 / 131
301 / 135 303 / 134
324 / 138 324 / 136
346 / 140 347 / 139
371 / 142 370 / 141
395 / 144 394 / 143
420 / 146 418 / 145
447 / 148 444 / 146
473 / 150 471 / 147
Compressor