YORK
Start-Up & Operation Guide | 5587001-YSG-A-520
17
Start-Up
EXAMPLE:
The suction pressure is 130 PSIG and the
suction line temperature is 57.0 F.
Suction line temperature
= 57.0°F
Saturation temperature for 130 PSIG = 45.0°F
Evaporator superheat
= 12.0°F
CAUTION
When adjusting the expansion valve, DO NOT turn
the adjusting screw more than one turn at a time.
Allow for sufficient time (approximately 15 minutes)
between adjustments for the system and the TXV
to respond and stabilize.
The superheat setting should be adjusted to 12.0°F at
design conditions.
Leak Checking
Leak check compressors, fittings, and piping to ensure
there are no leaks. Verify the evaporator distributor tubes
do not have bare copper touching each other and that
they are not against a sheet metal edge. If leak checking
a unit charged with R-410A, ensure the leak test device
is capable of sensing refrigerant R-410A.
If the unit is functioning satisfactorily during the initial
operating period, no safeties trip, and the unit controls
are properly functioning, the rooftop unit is ready to be
placed into operation.
Gas Heat Models
WARNING
ELECTRICAL SHOCK, FIRE, OR EXPLOSION
HAZARD
Failure to follow safety warnings exactly, as well as
improper servicing, can result in dangerous opera-
tion, serious injury, death, or property damage.
• Before servicing, disconnect all electrical
power to furnace.
• When servicing controls, label all wires prior
to disconnecting. Reconnect wires correctly.
• Verify proper operation after servicing.
Table 8: R-410A Pressure/Temperature Chart
PSIG
TEMP (
˚
F)
PSIG
TEMP (
˚
F)
PSIG
TEMP (
˚
F)
PSIG
TEMP (
˚
F)
0
-60
40
-6
80
21
210
73
2
-58
42
-4
85
24
220
76
4
-54
44
-3
90
26
225
78
6
-50
46
-2
95
29
235
80
8
-46
48
0
100
32
245
83
10
-42
50
1
105
34
255
85
12
-39
52
3
110
36
265
88
14
-36
54
4
115
39
275
90
16
-33
56
6
120
41
285
92
18
-30
58
7
125
43
295
95
20
-28
60
8
130
45
305
97
22
-26
62
10
135
47
325
101
24
-24
64
11
140
49
355
108
26
-20
66
13
145
51
375
112
28
-18
68
14
150
53
405
118
30
-16
70
15
160
57
500
134
32
-14
72
16
170
60
600
149
34
-12
74
17
180
64
700
159
36
-10
76
19
190
67
38
-8
78
20
200
70
