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XP16
Table 2. HFC−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
System Operation
The outdoor unit and indoor blower cycle on demand from
the room thermostat. When the thermostat blower switch is
in the
ON
position, the indoor blower operates continuously.
SECOND−STAGE OPERATION
If the board receives a call for second−stage compressor
operation Y2 in heating or cooling mode and the first-stage
compressor output is active, the second-stage compressor
solenoid output will be energized.
If first-stage compressor output is active in heating mode
and the outdoor ambient temperature is below the selected
compressor lock−in temperature, the second-stage
compressor solenoid output will be energized without the Y2
input. If the jumper is not connected to one of the
temperature selection pins on P3 (40, 45, 50, 55°F), the
default lock−in temperature of 40°F (4.5°C) will be used.
The board de−energizes the second-stage compressor
solenoid output immediately when the Y2 signal is removed
or the outdoor ambient temperature is 5°F above the
selected compressor lock−in temperature, or the first-stage
compressor output is de−energized for any reason.
THERMOSTAT OPERATION
Some indoor thermostats incorporate isolating contacts and
an emergency heat function (which includes an amber
indicating light). The thermostat is not included with the unit
and must be purchased separately.
EMERGENCY HEAT (AMBER LIGHT)
An emergency heat function is designed into some room
thermostats. This feature is applicable when isolation of the
outdoor unit is required, or when auxiliary electric heat is staged
by outdoor thermostats. When the room thermostat is placed in
the emergency heat position, the outdoor unit control circuit is
isolated from power and field-provided relays bypass the
outdoor thermostats. An amber indicating light simultaneously
comes on to remind the homeowner that he is operating in the
emergency heat mode.
Emergency heat is usually used during an outdoor unit
shutdown, but it should also be used following a power
outage if power has been off for over an hour and the outdoor
temperature is below 50°F (10°C). System should be left in
the emergency heat mode at least six hours to allow the
crankcase heater sufficient time to prevent compressor
slugging.
FILTER DRIER
The unit is equipped with a large−capacity bi−flow filter drier
which keeps the system clean and dry. If replacement is
necessary, order another of like design and capacity. The
replacement filter drier must be suitable for use with
HFC−410A refrigerant.
