Page 12
TABLE 4
R−410A Temperature (°F) − Pressure (Psig)
°F
Psig
°F
Psig
°F
Psig
°F
Psig
32
100.8
63
178.5
94
290.8
125
445.9
33
102.9
64
181.6
95
295.1
126
451.8
34
105.0
65
184.3
96
299.4
127
457.6
35
107.1
66
187.7
97
303.8
128
463.5
36
109.2
67
190.9
98
308.2
129
469.5
37
111.4
68
194.1
99
312.7
130
475.6
38
113.6
69
197.3
100
317.2
131
481.6
39
115.8
70
200.6
101
321.8
132
487.8
40
118.0
71
203.9
102
326.4
133
494.0
41
120.3
72
207.2
103
331.0
134
500.2
42
122.6
73
210.6
104
335.7
135
506.5
43
125.0
74
214.0
105
340.5
136
512.9
44
127.3
75
217.4
106
345.3
137
519.3
45
129.7
76
220.9
107
350.1
138
525.8
46
132.2
77
224.4
108
355.0
139
532.4
47
134.6
78
228.0
109
360.0
140
539.0
48
137.1
79
231.6
110
365.0
141
545.6
49
139.6
80
235.3
111
370.0
142
552.3
50
142.2
81
239.0
112
375.1
143
559.1
51
144.8
82
242.7
113
380.2
144
565.9
52
147.4
83
246.5
114
385.4
145
572.8
53
150.1
84
250.3
115
390.7
146
579.8
54
152.8
85
254.1
116
396.0
147
586.8
55
155.5
86
258.0
117
401.3
148
593.8
56
158.2
87
262.0
118
406.7
149
601.0
57
161.0
88
266.0
119
412.2
150
608.1
58
163.9
89
270.0
120
417.7
151
615.4
59
166.7
90
274.1
121
423.2
152
622.7
60
169.6
91
278.2
122
428.8
153
630.1
61
172.6
92
282.3
123
434.5
154
637.5
62
175.4
93
286.5
124
440.2
155
645.0
4. Subtract the liquid line temperature from the saturation
temperature (according to the chart) to determine the
subcooling value.
5. Compare the subcooling value with those in table 5. If
subcooling value is greater than shown, recover some
refrigerant; if less, add some refrigerant.
TABLE 5
XP13 Subcooling Values for Charging
Saturation Temperature
Liquid Line Temperature
=
Subcooling Value
Model
−018
−024
−030
−036
−037
−042
−048
−060
°F
(°C)*
6
(3.3)
3
(1.7)
7
(3.9)
4
(2.2)
4
(2.2)
5
(2.8)
7
(3.9)
7
(3.9)
*F: +/−1.0°; C: +/−0.5°
Charge Using the Approach Method
Outdoor
Temperature > 65ºF (18ºC)
The following procedure is intended as a general guide and
is for use on expansion valve systems only. For best results,
indoor temperature should be 70°F (21°C) to 80°F (26°C).
Monitor system pressures while charging.
1. Check the outdoor ambient temperature using a digital
thermometer and record in table 6.
2. Attach high pressure gauge set and operate unit for
several minutes to allow system pressures to stabilize.
3. Compare stabilized pressures with those provided in
table 7, Normal Operating Pressures." Minor varia-
tions in these pressures may be expected due to differ-
ences in installations. Significant differences could
mean that the system is not properly charged or that a
problem exists with some component in the system.
Pressures higher than those listed indicate that the sys-
tem is overcharged. Pressures lower than those listed
indicate that the system is undercharged. Continue to
check adjusted charge using approach values.
4. Use the same digital thermometer used to check out-
door ambient temperature to check liquid line tempera-
ture and record in table 6. Verify the unit charge using
the approach method. The difference between the am-
bient and liquid temperatures should match values giv-
en in table 6. Add refrigerant to lower the approach tem-
perature and remove it to increase the approach tem-
perature. Loss of charge results in low capacity and ef-
ficiency.
5. If the values do not agree with those in table 6, add re-
frigerant to lower the approach temperature or recover
refrigerant from the system to increase the approach
temperature.
TABLE 6
XP13 Approach Values for Charging
Liquid Line Temperature
Outdoor Temperature
=
Approach Temperature
Model
−018
−024
−030
−036
−037
−042
−048
−060
°F (°C)*
7
(3.9)
11
(6)
11
(6)
15
(8.3)
12
(6.7)
11
(6)
9 (5)
12
(6.7)
NOTE − For best results, use the same electronic thermometer to
check both outdoor-ambient and liquid-line temperatures.
*F: +/−1.0°; C: +/−0.5°
