Care And Maintenance - Carrier 38BYC Installation And Start-Up Instructions Manual

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OF1
O R T2 Y
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CES0110063,
CES0130024
Fig. 15—Defrost Control
Table 3—Defrost Control Speed-Up
Timing Sequence
MINIMUM
PARAMETER
(MINUTES)
30-minute cycle 27
50-minute cycle 45
90-minute cycle 81
10-minute cycle
5 minutes 4.5
→
COOLING ONLY PROCEDURE
NOTE: If subcooling charging conditions are not favorable,
charge must be weighed in accordance with unit rating plate ± 0.6
oz/ft of 3/8-in. liquid line above or below 15 ft respectively.
EXAMPLE:
To calculate additional charge required for a 25-ft line set:
25 ft - 15 ft = 10 ft X 0.6 oz/ft = 6 oz of additional charge
Units installed with cooling mode TXV require charging with the
subcooling method.
1. Operate unit a minimum of 10 minutes before checking
charge.
2. Measure liquid service valve pressure by attaching an accurate
gage to service port.
3. Measure liquid line temperature by attaching an accurate
thermistor type or electronic thermometer to liquid line near
outdoor coil.
4. Refer to unit rating plate for required subcooling temperature.
5. Refer to Table 4. Find the point where required subcooling
temperature intersects measured liquid service valve pressure.
6. To obtain required subcooling temperature at a specific liquid
line pressure, add refrigerant if liquid line temperature is
higher than indicated or reclaim refrigerant if temperature is
lower. Allow a tolerance of ± 3°F.
Copyright 1997 CARRIER Corp. • 7310 W. Morris St. • Indianapolis, IN 46231
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4
PC 101 Catalog No. 563-853
Tab 5a 5a
TI DFT C TEST 30 50 90
W1
MAXIMUM SPEED-UP
(MINUTES) (NOMINAL)
33 7 sec
55 12 sec
99 21 sec
9 11 2 sec
5.5 1 sec
Printed in U.S.A.
Table 4—Required Liquid-Line Temperature (°F)
LIQUID
PRESSURE AT
SERVICE VALVE
(PSIG)
134
141
148
156
163
171
179
187
196
205
214
223
233
243
253
264
A91444 274
285
297
309
321
331
346
359
HEATING CHECK CHART PROCEDURE
To check system operation during heating cycle, refer to the
Heating Check Chart on outdoor unit. This chart indicates whether
a correct relationship exists between system operating pressure and
air temperature entering indoor and outdoor units. If pressure and
temperature do not match on chart, system refrigerant charge may
not be correct. Do not use chart to adjust refrigerant charge.
NOTE: When charging is necessary during heating season,
charge must be weighed in accordance with unit rating plate ± 0.6
oz/ft of 3/8-in. liquid line above or below 15 ft respectively.
EXAMPLE:
To calculate additional charge required for a 25-ft line set:
25 ft - 15 ft = 10 ft X 0.6 oz/ft = 6 oz of additional charge
→
Step 15—Final Checks
IMPORTANT: Before leaving job, be sure to do the following:
1. Securely fasten all panels and covers.
2. Tighten service valve stem caps to 1/12-turn past finger tight.
3. Leave User's Manual with owner. Explain system operation
and periodic maintenance requirements outlined in manual.
4. Fill out Dealer Installation Checklist and place in customer
file.
For continuing high performance and to minimize possible equip-
ment failure, periodic maintenance must be performed on this
equipment.
Frequency of maintenance may vary depending upon geographic
areas, such as coastal applications.
Form 38BYC-1SI
REQUIRED SUBCOOLING
TEMPERATURE
(°F)
5 10
71 66
74 69
77 72
80 75
83 78
86 81
89 84
92 87
95 90
98 93
101 96
104 99
107 102
110 105
113 108
116 111
119 114
122 117
125 120
128 123
131 126
134 129
137 132
140 135

CARE AND MAINTENANCE

Pg 12 10-97 Replaces: 38AYC-1SI/38-6SM
15 20
61 56
64 59
67 62
70 65
73 68
76 71
79 74
82 77
85 80
88 83
91 86
94 89
97 92
100 95
103 98
106 101
109 104
112 107
115 110
118 113
121 116
124 119
127 122
130 125
38byc1si