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manuals
\manuals 2019\s90refcool
manuals\s90installation-maintenance pasteuriser manual 3.12.2019.doc
Date Printed: 03/12/2019
Page No.
50
WATER REFRIGERATION SYSTEM
From the Flow Diagram in the appendix the circuits can
be clearly seen. The water circuit can be repaired and
adjusted by a skilled fitter or electrician.
The refrigeration system requires a specialist. However,
there are certain checks which can be made to determine
refrigeration fault.
i) Are fan and compressor running?
If not, check overloads and starter.
ii) If running but not cooling, check refrigerant liquid
sight glass.
If violent bubbling, shortage of gas.
If clear, no gas or all liquid.
Check gas line solenoid valve. When switched on a
light screw driver will be affected by magnetism from
the coil. If satisfactory, check drier and expansion
valve.
Drier: Sometimes this can become blocked. A good drier has
the same temperature at both ends. A blocked drier will
be warm at the entry end and cold at the exit end. If
faulty, call a refrigeration engineer.
Expansion Valve: There should not be any frosting on this valve. Frosting
would indicate a gas shortage.
Call a refrigeration engineer.
Hot Air: Hot air from the condenser indicates all is working well.
Slightly warm air indicates low performance. This will
eventually be traced to any of the above tests.
Gassing: Information for refrigeration engineer. Lightly gas with
R134A
until sight glass is just clear.
Maintenance Sequence:
The Electrical Panel Fills the bath with water and turns on
the heater and the chillier alternately. The chillier is
controlled by the Chill set point. The heater runs for a
fixed time after the bath reaches the cooling set point.
This procedure will allow a refrigeration engineer to
diagnose and correct any fault related to the refrigeration
circuit.