CHARGING INFORMATION
FOR COMPLETE CHARGING DETAILS, REFER TO THE OUTDOOR UNIT INSTALLATION INSTUCTION.
AIRFLOW CHECK - Both airflow and refrigerant charge must be monitored
for a proper system set‐up. It may be necessary to alternately check and
adjust the airflow and the refrigerant charge.
NOTE - Be sure that filters and indoor and outdoor coils are clean before testing.
To determine temperature drop across indoor coil (Delta-T), measure the entering air dry
bulb (DB) and wet bulb (WB) temperatures at the indoor coil. Find Delta-T in table 1. Measure
coil's leaving air DB and subtract that value from entering air DB. The measured difference
should be 3ºF (+1.8ºC) of table value; if too low, decrease the indoor fan speed (refer
to indoor unit for information). If the Delta-T is too high, increase the indoor fan speed. Repeat
charging procedure and Delta-T (air flow adjustment) procedure until both are correct.
Example:
assume entering air DB - 72, WB - 64, leaving DB - 53. Therefore, Delta-T should
be 15 (per table); delta across coil is 72 - 53 or 19 (which is 4ºF higher than table value); action
necessary: increase fan speed.
Table 1. Evaporator Coil Delta-T
Dry bulb
80
24 24 24 23 23 22 22 22 20 19 18 17 16 15
temperature
78
23 23 23 22 22 21 21 20 19 18 17 16 15 14
of air
76
22 22 22 21 21 20 19 19 18 17 16 15 14 13
entering
74
21 21 21 20 19 19 18 17 16 16 15 14 13 12
indoor
72
20 20 19 18 17 17 16 15 15 14 13 12 11 10
coil (ºF)
70
19 19 18 18 17 17 16 15 15 14 13 12 11 10
ºF 57 58 59 60 61 62 63 64 65 66 67 68 69 70
[
Wet bulb temperature of air entering indoor coil
]
Table 2. Superheat (SH) Value
RFC System - +5ºF
40
15 18 20 23 26 29 32 34 38 41 43 46 48 51
45
13 16 18 21 24 27 30 33 36 39 41 44 46 49
50
11 14 16 19 22 25 28 31 34 37 39 42 44 47
Dry bulb
55
9
12 14 17 20 23 27 30 33 36 38 40 42 44
temperature
66
7
10 12 15 18 21 24 27 30 33 35 38 40 43
of ambient
65
‐
6
10 13 16 19 21 24 27 30 33 36 38 41
air entering
70
‐
‐
7
10 13 16 19 21 24 27 30 33 36 39
outdoor
75
‐
‐
‐
6
9
12 15 18 21 24 28 31 34 37
unit (ºF)
80
‐
‐
‐
‐
5
8
12 15 18 21 25 28 31 35
85
‐
‐
‐
‐
‐
‐
8
11 15 19 22 26 30 33
90
‐
‐
‐
‐
‐
‐
5
9
13 16 20 24 27 31
95
‐
‐
‐
‐
‐
‐
‐
6
10 14 18 22 25 29
100
‐
‐
‐
‐
‐
‐
‐
‐
8
12 16 21 24 28
105
‐
‐
‐
‐
‐
‐
‐
‐
5
9
13 17 22 26
110
‐
‐
‐
‐
‐
‐
‐
‐
‐
6
11 15 20 25
115
‐
‐
‐
‐
‐
‐
‐
‐
‐
‐
8
14 18 24
ºF 50 52 54 56 58 60 62 64 66 68 70 72 74 76
[
Wet bulb temperature of air entering indoor coil
]
Mo
del
-18
-24
-30
-36
-42
-48
-60
Table 3. Normal Operating Pressures
1
°F(°C)
2
TXV System
- Liquid Line (+10 psig) / Vapor Line (+5 psig)
65 (18)
233 / 132
244 / 137
248 / 127
263 / 135
250 / 135
240 / 130
242 / 130
70 (21)
251 / 133
263 / 138
263 / 131
281 / 138
268 / 137
257 / 131
266 / 131
75 (24)
265 / 133
285 / 139
284 / 132
302 / 140
288 / 138
278 / 132
286 / 132
80 (27)
292 / 135
307 / 140
307 / 134
325 / 142
310 / 139
299 / 133
309 / 133
85 (29)
314 / 136
329 / 141
330 / 135
349 / 142
332 / 140
323 / 134
332 / 134
90 (32)
338 / 137
354 / 142
355 / 136
375 / 143
356 / 140
344 / 135
357 / 135
95 (35)
362 / 138
379 / 143
380 / 137
404 / 144
381 / 141
369 / 136
381 / 136
100 (38)
388 / 140
404 / 144
407 / 138
433 / 145
406 / 143
394 / 137
407 / 137
105 (41)
415 / 141
438 / 145
434 / 139
462 / 147
432 / 143
418 / 139
433 / 138
110 (43)
444 / 142
464 / 147
465 / 141
494 / 149
459 / 145
446 / 140
459 / 140
115 (45)
475 / 143
495 / 148
497 / 142
527 / 150
490 / 145
477 / 141
488 / 141
°F(°C)
2
Fixed Orifice (RFC)
- Liquid Line (+10 psig) / Vapor Line (+5 psig)
65 (18)
233 / 121
246 / 126
245 / 123
261 / 134
250 / 135
248 / 127
255 / 126
70 (21)
250 / 124
265 / 129
265 / 126
281 / 136
268 / 137
266 / 130
274 / 128
75 (24)
270 / 128
286 / 132
286 / 129
301 / 138
288 / 138
284 / 132
294 / 131
80 (27)
291 / 131
307 /135
308 / 132
324 / 140
310 / 139
305 / 134
317 / 134
85 (29)
313 / 134
330 / 137
331 / 135
346 / 142
332 / 140
325 / 137
339 / 136
90 (32)
335 / 136
353 / 140
355 / 138
371 / 144
356 / 140
347 / 139
362 / 138
95 (35)
359 / 138
378 / 142
380 / 140
396 / 146
381 / 141
371 / 141
386 / 140
100 (38)
383 / 140
402 / 143
405 / 142
422 / 148
406 / 143
394 / 143
413 / 142
105 (41)
409 / 142
428 / 145
431 / 144
448 / 150
432 / 143
418 / 144
435 / 144
110 (43)
436 / 145
456 / 147
458 / 146
477 / 151
459 / 145
445 / 146
462 / 146
115 (46)
464 / 147
486 / 149
487 / 148
506 / 153
490 / 145
472 / 147
490 / 148
Table 4. Approach (APP) Values
3
-
TXV System - ºF (ºC) +1ºF (0.5ºC)
All
4 (2.2)
8 (4.4)
8 (4.4)
11 (6.1)
10 (5.6)
6 (3.3)
9 (5.0)
Table 5. Subcooling (SC) Values
4
-
TXV System - ºF (ºC) +1ºF (0.5ºC)
All
10 (5.6)
10 (5.6)
9 (5.0)
12 (6.7)
8 (4.4)
10 (5.6)
7 (3.9)
1
Typical pressures; indoor evaporator match up, indoor air quantity, and evaporator load will cause
the pressures to vary.
2
Temperature of air entering outside coil.
3
Approach = Liquid Line Temp. minus Outdoor Ambient Temperature
4
Subcooling = Saturation Temp. minus Liquid Line Temp Temperature
*2P1107*
*P401288S*
11/07
401288S
