Refrigeration System Service: Hp62 - Scotsman SCE170 User Manual

Refrigeration System Service: HP62 (R-404A)
This ice machine uses R-404A refrigerant and
polyolester oil. Do NOT use mineral oil in this
refrigeration system.
R-404A is a "Near Azeotrope" so liquid
charging is required:
¤
Weigh in as liquid as much of the charge as
possible into the discharge line.
¤
Install a sight glass between the manifold and
the suction side hose and carefully meter
liquid into the suction side, using the manifold
valve to "flash off" the liquid before it enters
the ice machine. Do this until the proper
amount of refrigerant has been weighed into
the system.
When the system is serviced, a special liquid
line drier is required. It is included with
replacement compressors.
HP62 is not compatable with mineral oil, so
these ice machines use Polyolester oil.
Polyolester oil absorbs water very easily. When
one of these refrigeration systems is opened for
service, it must be re-sealed as soon as
possible (15 minutes maximum).
Special leak detection equipment is required to
locate small refrigerant leaks. Usually a leak
detector capable of dectecting a Halongenated
refrigerant or HFC-134A will work. Check with
the leak detector manufacturer if in doubt.
Pressure-Temperature Chart for HP62
VAPOR
TEMP. PRESSURE
(DEG F)
-20 . . . . . . 17
-18 . . . . . . 18
-16 . . . . . . 20
-14 . . . . . . 21
-12 . . . . . . 23
-10 . . . . . . 24
-8 . . . . . . . 26
-6 . . . . . . . 28
-4 . . . . . . . 29
-2 . . . . . . . 31
0 . . . . . . . 33
2 . . . . . . . 35
4 . . . . . . . 37
6 . . . . . . . 39
8 . . . . . . . 41
10 . . . . . . . 43
12 . . . . . . . 46
14 . . . . . . . 48
16 . . . . . . . 50
18 . . . . . . . 53
20 . . . . . . . 55
22 . . . . . . . 58
24 . . . . . . . 60
26 . . . . . . . 63
28 . . . . . . . 66
30 . . . . . . . 69
32 . . . . . . . 72
34 . . . . . . . 75
36 . . . . . . . 78
38 . . . . . . . 81
40 . . . . . . . 85
42 . . . . . . . 88
44 . . . . . . . 91
46 . . . . . . . 95
48 . . . . . . . 99
50 . . . . . . . 102
52 . . . . . . . 106
54 . . . . . . . 110
56 . . . . . . . 114
58 . . . . . . . 118
60 . . . . . . . 123
62 . . . . . . . 127
64 . . . . . . . 132
66 . . . . . . . 136
68 . . . . . . . 141
October 1998
Page 29
SCE170
TEMP.
(PSIG) (DEG F)
70 . . . . . . . 146
72 . . . . . . . 150
74 . . . . . . . 155
76 . . . . . . . 161
78 . . . . . . . 166
80 . . . . . . . 171
82 . . . . . . . 177
84 . . . . . . . 182
86 . . . . . . . 188
88 . . . . . . . 194
90 . . . . . . . 200
92 . . . . . . . 206
94 . . . . . . . 212
96 . . . . . . . 219
98 . . . . . . . 225
100 . . . . . . 232
102 . . . . . . 239
104 . . . . . . 246
106 . . . . . . 253
108 . . . . . . 260
110 . . . . . . 268
112 . . . . . . 275
114 . . . . . . 283
116 . . . . . . 291
118 . . . . . . 299
120 . . . . . . 307
122 . . . . . . 316
124 . . . . . . 324
126 . . . . . . 333
128 . . . . . . 342
130 . . . . . . 351
132 . . . . . . 360
134 . . . . . . 370
136 . . . . . . 379
138 . . . . . . 389
140 . . . . . . 399
142 . . . . . . 409
144 . . . . . . 420
146 . . . . . . 430
148 . . . . . . 441
150 . . . . . . 452
152 . . . . . . 464
154 . . . . . . 475
156 . . . . . . 487
158 . . . . . . 499
VAPOR
PRESSURE
(PSIG)