Hussmann ISCGG-D, Инструкция по установке и обслуживанию

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Page 10
PIPING INSULATION
For refrigerators with other than KOOLGAS defrost, the suction and liquid lines should be
clamped and/or taped together and insulated for a minimum of 30 feet from the refrigerator.
Refrigerators with KOOLGAS defrost should not have their liquid and suction lines in contact
with each other but are to be separately insulated for a minimum of 30 feet from the refrigerator.
Additional insulation for the balance of the refrigerant lines is recommended and required
wherever condensation and dripping would be objectionable.
EXPANSION VALVE ADJUSTMENT
Expansion valves must be adjusted to fully feed the evaporator. Before attempting to adjust
valves, make sure the evaporator is either clear of / or only lightly covered with frost, and that
the fixture is within 10
°
F of it’s expected operating temperature.
Adjust the valve as follows :
Attach two sensing probes (either thermocouple or thermistor type) to the evaporator. One
under the clamp holding the expansion valve bulb and the other securely taped to an evaporator
coil return bend about ½ way through the coil.
OR
A) Attach a probe to the suction line near the expansion valve
B) Obtain a pressure reading from the factory Schraeder valve
Convert the pressure reading to a saturated temperature for the appropriate
refrigerant.
Temperature B minus Temperature A = Super Heat
Some “hunting” of the expansion valve is normal. The valve should be adjusted so that during
the hunting
the greatest difference between the two temperatures is 3
°
F to 5
°
F .
With this adjustment, during a portion of the hunting the temperature difference between the
probes will be less than 3
°
F (at times as low as 0
°
F).
Make adjustments of no more than (1/2) turn of the valve stem at a time and wait for at
least fifteen minutes before checking the probe temperature again and making further
adjustments
.