Refrigeration Service: R-404A (Hp62) - Scotsman TDE550 Service Manual

TDE550 & TDE650

REFRIGERATION SERVICE: R-404A (HP62)

THIS ICE MACHINE USES HP62 REFRIGERANT
AND POLYOLESTER COMPRESSOR OIL.
DO NOT USE MINERAL OIL IN THIS
REFRIGERATION SYSTEM.
R-404A is a "Near Azeotrope", and therefore
liquid charging is required.
Weigh into the discharge side as much as possible
of the charge as liquid refrigerant.
Install a sight glass between the manifold and the
suction side hose. Carefully meter liquid refrigerant
into the suction side, using the manifold valve to
"flash off" the liquid before it enters the ice
machine. Do this until the proper charge has been
weighed into the system.
When the system is serviced, a special liquid
line dryer is required.
Polyolester oil absorbs water very easily, and
therefore when the system 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
Halogenated refrigerant or HFC-134A will
work. Check with the leak detector
manufacturer if in doubt.
As with any other refrigerant, do NOT mix
HP62 with pressurized air when leak testing.
Pressure-Temperature Chart for HP62
VAPOR
TEMP. PRESSURE
(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
August 1999
Page 30
VAPOR
TEMP. PRESSURE
(DEG F) (PSIG)
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