Zero Zone 3RMCC30WA, Руководство по установке и эксплуатации

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GENERAL INFORMATION
LIGHT SWITCH
The light switch is located inside the right-hand door. Turn the light switch off during the initial case temperature pull down to prevent the
case lights from cycling off and on. Always turn the lights off when replacing lamps.
CASE THERMOMETER
The cases are shipped with 2 thermometers. One thermometer is factory mounted in the discharge air stream. The second thermometer
is shipped loose and should be installed in the warmest product location. Specific instructions are packaged with the shipped loose
thermometer.
SERVICE
See Figure 33 on page 41 and Figure 35 on page 43 for the typical component layout of the 30" door case. See Figure 34 on
page 41 and Figure 36 on page 43 for the typical component layout of the 24" door cases.
The bumper and kickplate must be removed to gain access to the drain clean out and electrical connections. Disassemble the bumper
and kickplate by removing the 2 or 3 metal screws located in the kick rail. The bumper assembly can be lifted up and removed from the
case. The kickplate can be removed, exposing the electric tray cover and drain (
Figure 17 on page 18
).
EVAPORATOR
The evaporator coil, located at the rear bottom of the case, is factory assembled with distributor, expansion valve, and other refrigeration
components. To inspect the coil, remove the center or left of center coil cover. A small inspection window is located at the rear of the
case. To inspect the entire coil, remove the remaining coil covers and raise the evaporator cover.
EXPANSION VALVE
Unless otherwise specified, a superheat adjustable externally equalized thermostatic expansion valve with a removable strainer and
pressure limiting charge (low temp only) is mounted to the evaporator coil. The valve is not preset. Adjust the superheat setting for
maximum coil effectiveness. Typical superheat settings are between 6°F and 10°F. Close coupled systems should use the higher
superheat setting to minimize the chance of liquid flood back. To adjust the expansion valve, remove the right end coil cover. Remove the
cap from the bottom of the valve. When looking at the valve stem end, turn the valve stem counterclockwise to decrease superheat. Turn
the valve stem clockwise to increase super heat. Measure the suction line temperature at the expansion valve sensing bulb and compare
it to the suction temperature corresponding to the saturated pressure. Make sure that line pressure drop is taken into account.
Turn the valve stem only ¼ turn at a time and allow sufficient time (20 to 30 minutes) for the valve to settle before making any further
adjustments. Replace the valve stem cap after the valve superheat has been adjusted. BE CERTAIN THE VALVE STEM CAP IS WIPED
DRY FIRST.
!
Caution!
DISCONNECT POWER TO THE CASE BEFORE SERVICING ELECTRICAL COMPONENTS TO AVOID
PERSONAL INJURY AND DAMAGE TO THE UNIT.
EVAPORATOR FANS
Air is circulated throughout the case with 115 volt low temperature fan motors. These motors must be operating at all times except during
defrost in low temp cases. Fan motors should be replaced with motors having the same characteristics including type, physical size,
lubricant temperature range, wattage and RPM. Fan blades should be replaced with factory original equipment part.
General Information • 21