Temperature / Pressure Charts; Refrigeration System Adjustments; Expansion Valve; Adjustment And Troubleshooting - Cornelius WCC 2001 QT-R Service Manual

Continuous Flow Icemaker Service Manual
REFRIGERATION SYSTEM
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NOTE: The Thermostatic Expansion Valve is non-adjustable on all models.
R S
EFRIGERATION
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° to 90°F, depending on the season of the year.
Whenever a new icemaker product is initially installed and started–up, it is imperative that the start–up operation
make the following checks and/or readjustments for local conditions.
E V
XPANSION ALVE
You will find a thermostatic expansion valve on icemakers, 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 system troubleshooting along with the pressure charts you can easily determine
whether or not the expansion valve is working properly.
A
DJUSTMENT AND
When troubleshooting the expansion valve you must first be sure you have adequate water flowing into evaporator, a
clean condenser, unit is properly ventilated, and system is properly charged and free from any restrictions. Also be
sure compressor is operating properly.
Second, take reservoir water temperature and air temperature from condenser inlet and determine at what pressure
unit should be running. Machines are equipped with thermostatic valves, there is NO adjustment. If correct pressure
cannot be obtained, first be sure system has time to stabilize 10–15 minutes. Second, be sure sensing bulb is located
at 12:00 position on 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 system for possible problems. If proper charge is questionable evacuate and recharge to
nameplate and leak check. If valve still malfunctions replace valve.
When replacing valve be sure to bleed refrigerant gas from low side port so as not to lose refrigerant oil. Use general
refrigerant 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: Units with thermostatic expansion valve—valve is located on bottom refrigerant line.
Sensing bulb is located on top refrigerant line. On water cooled units adjust condenser modulating
valve before troubleshooting expansion valve.
Publication Number: 630460308SER
T
EMPERATURE
Refrigerant Type
R404A
50
60
70
80
90
100
A
YSTEM DJUSTMENTS
T
ROUBLESHOOTING
/ P
RESSURE CHARTS
WCC 2200
± 10 lbs. Discharge Pressure
Water Temperature (°F)
50 65
200 201
218 219
251 253
297 298
308 330
362 364
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90
203
220
254
300
332
366
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