Rev.0303
ACCESS TO TX VALVES AND DRAIN LINES
MECHANICAL - Remove product from case. Remove pans. TX valve (mechanical only) and drain are located under the pans within the case.
ELECTRONIC - The electronic expansion valve master and slave cylinder(s) are located within the electrical access panel(s) in the rear of case. Rear panels lift up and out.
NOTE: Duplex receptacles must be detached before removing rear panels.
ELECTRONIC EXPANSION VALVE (OPTIONAL)
A wide variety of electronic expansion valves and case controllers can be utilized. Please refer to EEV and controller Hussmann’s information sheet. Sensors for electronic expansion valves will be installed on the coil inlet, coil outlet, and in the discharge air. (Some supermarkets require a 4th sensor in the return air). Case controllers will be located in the electrical raceway or under the case.
THREE THERMOSTATIC EXPANSION VALVES
ALCO balanced port expansion valves are furnished as standard equipment, unless otherwise specified by customer.
EXPANSION VALVE ADJUSTMENT
Expansion valves must be adjusted to fully feed the evaporator. Before attempting any adjustments,make sure the evaporator is either clear or very lightly covered with frost, and that the fixture is within 10°F of its expected operating temperature.
After case has been brought to
running temperature, tighten glass screws
along clamshell.
pressure gauge at the evaporator outlet.
2.From a refrigerant pressure temperature chart, determine the saturation temperature at the observed suction pressure.
3.Measure the temperature of the suction gas at the thermostatic remote bulb location.
4.Subtract the saturation temperature obtained in step No. 2 from the temperature measured in step No.3.
3. The difference is superheat.
5. Set the superheat for 5°F - 7°F.
T-Stat
Electrical Raceway
MEASURING THE OPERATING SUPERHEAT
1. Determine the suction pressure with an accurate
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