Refrigeration System Service - Scotsman FME1200 Service Manual

REFRIGERATION SYSTEM SERVICE

General:
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:
When the system is serviced, a special liquid line drier is required. It is
included with replacement compressors.
HP62 is not compatible 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 detecting a Halongenated
refrigerant or HFC-134a will work. Check with the leak detector
manufacturer if in doubt.
Access Valves: To use the access valves:
Remove the cap from the stem, use a 3/16" allen wrench to check
that the valve is CLOSED. The remove the core cap.
Close the valve and replace the caps when the job is finished.
The valve must be closed and the caps must be on or the valve
will leak.
ALLEN
WRENCH
Torque to
6-8 ft. lb..
Cap, Torque
to 8-12 ft. lb..
ACCESS VALVE
Cap, Torque
to 7-11 ft. lb..
January 1995
Page 29
NME950 & FME1200
Pressure-Temperature Chart for HP62
VAPOR
TEMP. PRESS. TEMP. PRESS.
(DEG F) (PSIG) DEG F) (PSIG)
-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
VAPOR
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