Refrigeration (Cont'd)
Thermostatic Expansion Valve Location
This device is located on the same side as the refrigeration stub. An Alco balanced port expansion valve model is 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.
Measuring the Operating Superheat
1.Determine the suction pressure with an accurate 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.
5.The difference is superheat.
6.Set the superheat for 5°F - 7°F.
T-STAT Location
Thermostats are located within the electrical raceway. The raceway location is dependent on the style of the front panel and whether the case is going to be pushed up against a wall.
Front of Case
Ballast Location
Ballast and
In all cases, the thermostat is located on the same side of the case. If you are looking at the case from the front, it is the
It is the contractor’s responsibility to install case(s) according to local construction and health codes.
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