Flake Ice Machines
Refrigeration System
Page
F11
Mixing Valve Diagnosis:
Problem
Possible Cause
Remedy
Pump Down System (Remote Only)
a. Replace valve
a. Leak check. Recover
refrigerant and weigh
in proper charge.
b. Replace valve.
a. Replace valve.
a. Valve defective, not
allowing discharge
gas into receiver
a. System low on
charge.
b. Valve defective, not
allowing liquid into
receiver.
a. Valve defective, not
allowing refrigerant
through condenser.
1. Head pressure low,
Line between valve
and receiver cold.
Ambient condenser
temp. below 70
°
F
(21
°
C)
2. Head pressure low,
Line between valve
and receiver hot.
3. Head pressure low,
Line returning from
condenser is cool.
Ambient condenser
temperature is above
70
°
F (21
°
C)
The pump down system prevents liquid refrigerant from migrating to the evaporator and
compressor during the off cycle and prevents the compressor from slugging or starting under
an excessive load.
Liquid Line Solenoid
When a machine with a remote condenser shuts off, the liquid line
solenoid valve, located at the outlet of the receiver, is de-energized
causing the valve to close completely restricting the flow of refrigerant.
The compressor will pump all of the refrigerant into the condenser and
receiver.
As the system pumps down, the pressure on the low side of the system
drops. When the suction pressure drops to 19 psi (1.3 bar), the pump down control opens
and shuts the machine off. See page G5 for pump down control operation. Liquid refrigerant
is stored in the condenser and receiver while the machine is off. It is normal for the machine
to pump down once or twice an hour as the pressures equalize.
When the machine comes back on (the bin switch closes or the selector switch placed to the
ICE position), the liquid line solenoid valve opens and the refrigerant is released from the
receiver. When the suction pressure rises to 45 psi (3.1 bar) the pump down control closes
and the machine comes back on. If the machine will not pump down, the valve may not be
closing all the way. A weak compressor will also prevent the machine from pumping down.
Check for signs of a weak compressor before replacing the liquid line solenoid. Prior to
replacing the valve, disassemble and check for obstructions that may not allow the valve to
seat.
Summary of Contents for EF Series
Page 2: ......
Page 6: ......
Page 9: ...Flake Ice Machines General Information Page A7 EF Series ...
Page 10: ...Flake Ice Machines General Information Page A8 EMF Series ...
Page 11: ...Flake Ice Machines General Information Page A9 EMF Series 48 Inch Wide ...
Page 20: ...Flake Ice Machines Troubleshooting Trees Page C2 Machine Runs Does Not Make Ice ...
Page 21: ...Flake Ice Machines Troubleshooting Trees Page C3 Machine Runs Does Not Make Ice ...
Page 22: ...Flake Ice Machines Troubleshooting Trees Page C4 Machine Does Not Run ...
Page 23: ...Flake Ice Machines Troubleshooting Trees Page C5 Slow Production ...
Page 24: ...Flake Ice Machines Troubleshooting Trees Page C6 Low Production ...
Page 25: ...Flake Ice Machines Troubleshooting Trees Page C7 High Suction Pressure ...
Page 26: ...Flake Ice Machines Troubleshooting Trees Page C8 Machine Freezes Up Auger Seizes ...
Page 27: ...Flake Ice Machines Troubleshooting Trees Page C9 Auger Motor Amp Draw Fluctuates ...
Page 28: ...Flake Ice Machines Troubleshooting Trees Page C10 Water Leaking From Bottom of Evaporator ...
Page 29: ...Flake Ice Machines Troubleshooting Trees Page C11 Machine Produces Wet Ice ...
Page 31: ...Flake Ice Machines Troubleshooting Trees Page C13 Noise Coming from Evaporator ...
Page 41: ...Flake Ice Machines Drive System Page E8 Exploded View of the Evaporator ...
Page 43: ......
Page 46: ......
Page 61: ...Flake Ice Machines Electrical System Page G6 9071694 01 EF250 255 405 EF450A W ...
Page 62: ...Flake Ice Machines Electrical System Page G7 9071963 01 EF800A W ...
Page 63: ...Flake Ice Machines Electrical System Page G8 EMF450 405A W 9071958 01 ...
Page 64: ...Flake Ice Machines Electrical System G9 Page 9071954 01 EMF800A W ...
Page 65: ...Flake Ice Machines Electrical System Page G10 9071956 01 EMF705 1005 1006A W ...
Page 66: ...Flake Ice Machines Electrical System Page G11 9071962 01 EMF1106R ...
Page 67: ...Flake Ice Machines Electrical System Page G12 9071955 01 EMF2306A W ...
Page 68: ...Flake Ice Machines Electrical System Page G13 9071960 01 EMF2306R ...
Page 69: ...Flake Ice Machines Electrical System Page G14 9071959 01 EMF2305L ...
Page 70: ......
Page 71: ......
Page 72: ......