Freeze Cycle Operation All Models
The R404A headmaster valve is non adjustable.
At ambient temperatures of approximately 70°F (21°C) or
above, refrigerant flows through the valve from the
condenser to the receiver inlet. At temperatures below
this (or at higher temperatures if it is raining), the head
pressure control dome’s nitrogen charge closes the
condenser port and opens the bypass port from the
compressor discharge line.
In this modulating mode, the valve maintains minimum
head pressure by building up liquid in the condenser and
bypassing discharge gas directly to the receiver.
Harvest Cycle Operation
Remote Condenser Models
The headmaster valve cycles into full bypass due
to the pressure drop when the hot gas valve opens.
Refrigerant flows from the compressor to the evaporator
through the hot gas valve and the headmaster valve is
out of the circuit.
Diagnostics
FREEZE CYCLE - REMOTE CONDENSER
1. Determine if the coil is clean.
2. Determine the air temperature entering the
condenser.
3. Determine if the head pressure is high or low in
relationship to the outside temperature. (Refer to
the proper “Cycle Times/24-Hour Ice Production/
Refrigerant Pressure Charts” page 146).
4. Determine the temperature of the liquid line
entering the receiver by feeling it. This line is
normally warm; “body temperature.”
5. Using the information gathered, refer to the chart.
119
Summary of Contents for IM Series
Page 1: ...Revision Date 1 24 22 IM Series Air Water Remote Ice Machines Technician s Handbook ...
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Page 17: ...How to Read a Serial Number Full Serial Number 16 ...
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Page 48: ...Flexible Numeric Display FND Functions 47 ...
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Page 106: ...Testing the water level sensor Before S N Starting With VC 105 ...
Page 134: ...SERVICE REMOTE RECOVERY EVACUATION CONNECTIONS 133 ...
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Page 157: ...Wiring Diagram 156 ...
Page 158: ...PCB Layout 157 ...
Page 159: ...PCB Dip Switches 158 ...
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