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630460050SER
REFRIGERATION SYSTEMS
REFRIGERATION SYSTEM ADJUSTMENTS
A complete understanding of the icemaker and hermetic refrigeration system is necessary before any
adjustments are made. The refrigeration technician must use high and low side pressure readings, water and air
temperatures, plus general conditions of cleanliness to assess the refrigeration system status when making any
adjustments.
All icemaker products are tested and adjusted at the factory prior to shipment where the ambient temperature
ranges from 65
_
F to 90
_
F, depending on the season of the year.
Whenever a new icemaker is initially installed and started–up, it is imperative that the start–up operator make
the following checks and readjustments for local conditions.
EXPANSION VALVE
You will find a thermal expansion valve on Wilshire ice makers, which is used to control the amount of
refrigerant flowing through the evaporator. Improperly installed or defective expansion valves may cause low
production, soft ice, squeaking from evaporator and excessive load inside evaporator.
By using general refrigeration trouble shooting along with the pressure charts, you can easily determine whether
or not the expansion valve is working properly.
ADJUSTMENT AND TROUBLESHOOTING
When troubleshooting the expansion valve, you must;
1. Be sure you have adequate water flowing into the evaporator, a clean and properly ventilated condenser, and
the system is properly charged and free of any restrictions. Also be sure compressor is operating properly.
2. Take reservoir water temperature and air temperature from condenser inlet and determine at what pressure
unit should be running. On machines equipped with thermostatic valve there is NO adjustment. If correct
pressure cannot be obtained, be sure system has time to stabilize, 10–15 minutes.
3. Be sure sensing bulb is located at outlet side of evaporator about 3–4 inches away from evaporator and be
sure to insulate well and clamp tightly to tubing. If system pressures are still not adequate, take a second water
and air temperature reading and go over other parts of the system for possible problems. If proper charge is
questionable evacuate and recharge to nameplate and leak check. If valve still malfunctions replace valve.
Use general refrigeration system practices when replacing and recharging unit. After new valve is in place, go
through previous monitored adjustments and troubleshooting to be sure valve is functioning properly.
NOTE:
On water cooled units adjust condenser modulating valve before troubleshooting expansion
valve.
CAUTION: Very high discharge pressure is present in system. Quick disconnects on your
gages will minimize Danger and loss of refrigerant. Comply with federal regulations for
reclaiming refrigerant.
