CHARGING INFORMATION
FOR COMPLETE CHARGING DETAILS, REFER TO THE OUTDOOR UNIT INSTALLATION INSTRUCTIONS.
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.. Mea
sure coil's leaving air DB and subtract that value from entering air DB. The measured differ
ence 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 cor
rect.
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)
244 / 135
249 / 137
241 / 134
253 / 134
250 / 135
240 / 130
242 / 130
70 (21)
262 / 136
268 / 138
259 / 135
274 / 135
268 / 137
257 / 131
266 / 131
75 (24)
281 / 137
288 / 138
279 / 136
293 / 136
288 / 138
278 / 132
286 / 132
80 (27)
302 / 138
309 / 140
300 / 137
315 / 137
310 / 139
299 / 133
309 / 133
85 (29)
323 / 139
331 / 140
322 / 138
338 / 139
332 / 140
323 / 134
332 / 134
90 (32)
346 / 141
355 / 142
345 / 140
361 / 139
356 / 140
344 / 135
357 / 135
95 (35)
369 / 142
379 / 143
369 / 141
385 / 141
381 / 141
369 / 136
381 / 136
100 (38)
394 / 143
402 / 144
393 / 142
410 / 142
406 / 143
394 / 137
407 / 137
105 (41)
417 / 145
430 / 145
418 / 143
436 / 143
432 / 143
418 / 139
433 / 138
110 (43)
445 / 146
457 / 146
445 / 144
463 / 145
459 / 145
446 / 140
459 / 140
115 (45)
476 / 148
485 / 147
474 / 145
491 / 146
490 / 145
477 / 141
488 / 141
RFC System
- Liquid Line (+10 psig) / Vapor Line (+5 psig)
65 (18)
244 / 135
244 / 125
243 / 116
252 / 129
250 / 135
248 / 127
255 / 126
70 (21)
262 / 136
263 / 128
262 / 120
271 / 131
268 / 137
266 / 130
274 / 128
75 (24)
281 / 137
282 / 131
283 / 124
290 / 133
288 / 138
284 / 132
294 / 131
80 (27)
302 / 138
303 / 134
305 / 128
312 / 136
310 / 139
305 / 134
317 / 134
85 (29)
323 / 139
326 / 137
328 / 132
334 / 139
332 / 140
325 / 137
339 / 136
90 (32)
346 / 141
347 / 138
351 / 135
356 / 141
356 / 140
347 / 139
362 / 138
95 (35)
369 / 142
372 / 141
376 / 139
380 / 143
381 / 141
371 / 141
386 / 140
100 (38)
394 / 143
396 / 143
401 / 142
405 / 145
406 / 143
394 / 143
413 / 142
105 (41)
417 / 145
421 / 145
427 / 145
429 / 147
432 / 143
418 / 144
435 / 144
110 (43)
445 / 146
449 / 147
454 / 147
456 / 148
459 / 145
445 / 146
462 / 146
115 (46)
476 / 148
479 / 149
482 / 149
483 / 151
490 / 145
472 / 147
490 / 148
Table 4. Approach (APP) Values
3
-
TXV System - ºF (ºC) +1ºF (0.5ºC)
All
8 (4.5)
8 (4.5)
9 (5.0)
10 (5.6)
10 (5.6)
6 (3.3)
9 (5.0)
Table 5. Subcooling (SC) Values
4
-
TXV System - ºF (ºC) +1ºF (0.5ºC)
All
8 (4.1)
8 (4.1)
7 (3.8)
4 (2.2)
8 (4.4)
10 (5.6)
8 (4.4)
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
*2P0507*
*P401238S*
05/07
401238S
