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IV−Charging
System Performance
For maximum performance of this cooling system, the
operating temperatures and pressure should be checked
and subcooling determined at Standard ARI test conditions
of 82
_
F outdoor temperature / 80
_
F indoor dry bulb / 67
_
F
indoor wet bulb. If subcooling measured deviates from
values in table 6, refrigerant charge should be adjusted
accordingly for maximum performance.
TABLE 6
Subcooling Values
Unit Model No.
82
_
F OD / 80
_
F IDDB
/ 67
_
F IDWB
15CHAX−24
15CHAX−30
12
_
15CHAX−36
15
_
15CHAX−42
15CHAX−48
15CHAX−60
10
_
Verify system performance using table 7 as a general guide.
Table 7 should not be used for charging unit. Minor variations
in these pressures may be expected due to differences in
installations. Significant differences could mean that the sys-
tem is not properly charged or that a problem exists with
some component in the system.
Used carefully, this table could serve as a useful service
guide. Data is based on 80
°
F dry bulb / 67
°
F wet bulb return
air. Allow unit operation to stabilize before taking pressure
readings.
Table 7
Normal Operating Pressures
80
°
F db / 67
°
F wb RETURN AIR
Air Temperature Entering Outdoor Coil (
°
F)
UNIT
PRESSURE
65
70
75
80
82
85
90
95
100
105
110
115
15CHAX−24
142
143
144
146
146
147
148
149
150
151
152
153
15CHAX−30
134
136
138
140
141
142
144
146
148
149
151
152
15CHAX−36
Suction
143
144
146
147
148
149
151
152
155
155
157
157
15CHAX−42
Suction
140
140
140
141
141
141
142
142
143
144
145
147
15CHAX−48
140
141
142
144
144
145
146
147
148
149
150
151
15CHAX−60
143
144
145
146
146
147
147
148
149
150
151
152
15CHAX−24
219
242
264
287
296
310
333
355
379
398
430
457
15CHAX−30
232
255
277
300
309
323
345
368
390
408
440
470
15CHAX−36
Liquid
244
268
292
316
326
340
363
369
410
429
461
493
15CHAX−42
Liquid
225
247
269
291
300
314
337
357
383
402
434
457
15CHAX−48
243
264
285
307
315
328
349
370
391
408
440
470
15CHAX−60
257
280
303
326
335
349
372
395
418
436
468
497
V−Maintenance
At the start of each cooling season, this equipment should
be serviced by a qualified technician. Periodic inspection
and maintenance normally consists of changing or cleaning
filters.
Filters
Not supplied. Inspect once a month. Replace disposable or
clean permanent type as necessary. DO NOT replace per-
manent type with disposable.
Motors
Indoor, outdoor fan and vent motors are permanently
lubricated and require no further lubrication. Motors
should be cleaned yearly to prevent the accumulation of
dust and dirt on the windings or motor exterior.
Coil
Dirt and debris should not be allowed to accumulate on the
coil surfaces or other parts in the air conditioning circuit.
Cleaning should be performed as often as necessary. Use a
brush, vacuum cleaner attachment, or other suitable
means. If water is used to clean the coil, be sure the power
to unit is shut off prior to cleaning.
NOTE − Care should be used when cleaning the coil so that
the coil fins are not damaged.
Do not permit the hot condenser air discharge to be ob-
structed by overhanging structures or shrubs.
