Manual 2100-749
Page
44 of 68
Pressure Service Ports
High and low pressure service ports are installed on all
wall-mount units so that the system operating pressures
can be observed. Pressures are shown in Table 12.
This unit employs high-flow Coremax valves instead of
the typical Schrader type valves.
WARNING! Do NOT use a Schrader valve core removal
tool with these valves. Use of such a tool could result
in eye injuries or refrigerant burns!
To change a Coremax valve without first removing the
refrigerant, a special tool is required which can be
obtained at www.fastestinc.com/en/SCCA07H. See the
replacement parts manual for replacement core part
numbers.
TABLE 12
W180 Cooling Pressures (S, T, Q and N Voltage Models)
Low side pressure ± 4 PSIG
High side pressure ± 10 PSIG
1
Stage 3 is circuit 1
fully loaded
and circuit 2
on
.
2
Stage 2 is circuit 1
unloaded
and circuit 2
on
.
3
Stage 1 is circuit 1
unloaded
and circuit 2
off
.
Tables are based upon
rated CFM
(airflow) across the evaporator coil. If there is any doubt as to correct operating charge
being in the system, the charge should be removed and system evacuated and recharged to serial plate charge weight.
NOTE:
Pressure table based on high speed condenser fan operation. If condensing pressures appear elevated, check
condenser fan wiring. See
Condenser Fan Operation
on page 25.
Cooling Air Temperature Entering Outdoor Coil °F
Model
Return Air Temp
(DB/WB)
Pressure
75
80
85
90
95
100 105 110 115 120 125 131
W180
Stage 3
1
75°/62°
Low Side
126 127 128 129 130 131 132 133 134 135 136 138
High Side
315 340 364 388 412 435 459 481 504 526 548 573
80°/67°
Low Side
135 136 137 138 139 140 141 142 143 145 146 147
High Side
323 348 374 398 423 447 470 494 517 539 562 588
85°/72°
Low Side
140 141 142 143 144 145 146 147 148 150 151 152
High Side
334 361 387 412 437 462 487 511 535 558 581 609
W180
Stage 2
2
75°/62°
Low Side
138 140 141 142 143 143 143 142 141 140 138 136
High Side
318 342 365 389 412 435 458 480 502 524 545 570
80°/67°
Low Side
148 150 151 152 153 153 153 152 151 150 148 145
High Side
326 350 375 399 423 446 469 492 515 537 559 585
85°/72°
Low Side
153 155 156 157 158 158 158 157 156 155 153 150
High Side
337 363 388 413 438 462 486 509 533 556 579 605
W180
Stage 1
3
75°/62°
Low Side
129 130 130 131 132 133 135 136 137 138 139 141
High Side
312 341 367 392 415 435 454 470 485 497 508 518
80°/67°
Low Side
138 139 140 141 142 143 144 145 146 148 149 151
High Side
320 350 377 402 425 446 465 482 497 510 521 531
85°/72°
Low Side
142 143 144 145 147 148 149 150 152 153 154 156
High Side
332 362 390 416 440 462 482 499 515 528 539 550
