Refrigeration System - Scotsman FDE474 User Manual

Refrigeration System

This ice machine uses R-134a as the
refrigerant. This refrigerant has no chlorine,
and therefore requires polyolester type
refrigerant oil. This oil requires specific service
procedures.
General Service
A HFC type liquid line drier is required. "Standard"
driers may not take out enough moisture and may
affect the oil additives.
The time that the refrigeration system is open to
the air must not exceed 15 minutes. The oil will
rapidly absorb moisture from the air, and the
contact time must be kept to a minimum.
A special or very sensitive electronic leak detector
will be needed to locate refrigerant leaks. Many are
on the market that will sense R-134a.
The access valves must be in the closed position
before the hose caps are removed. Do not remove
the hose caps before checking the position of the
valve. Use a 3/16" allen wrench to open and close
the valve.
Torque Stem to
6-8 ft. lb.
Access Valve
As with any other refrigerant, do not place
pressurized air or oxygen into the refrigeration
system.
Note: The refrigeration system uses an HFC type
refrigerant and MUST use an HFC type drier.
Evacuation to 300 microns is recommended.
Stem Cap
Torque to 8-12 ft. lb.
Fitting Cap
Torque to 7-12 ft. lb.
March 2000
Page 27
Temperature Pressure Chart, Selected Points
0
Temperature in F.
-10
-6
-4
-2
0
1
2
3
4
5
10
12
14
16
18
20
25
30
31
32
33
34
35
40
45
50
75
90
110
120
130
150
FDE474
PSIG of R-134a
2.0
3.7
4.6
5.5
6.5
7.0
7.5
8.0
8.6
9.1
12.0
13.2
14.4
15.7
17.1
18.4
22.1
26.1
26.9
27.8
28.6
29.5
30.4
35.0
40.0
45.4
78.7
104.3
146.4
171.1
198.7
262.8