0-UC 13-FEB 18-2
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5
PIPING INSTALLATION
5.1
Refrigerant pipe connection
Refrigerant pipe connections should be installed in accordance with all the applicable codes and using good
refrigeration practices. Suction lines should be properly insulated to prevent sweating and ensure only
superheated vapor is returned to compressor suction. During brazing, the system should be purged with
nitrogen first, to prevent oxidation.
5.2
Vacuum and leak test
When all refrigeration piping connections had been completed, the entire system must be tested for leaks
and then vacuum. Refer to the instruction manual provided by the coupled condensing unit for the leak test
and vacuum test information.
5.3
Drain pipe
Installing a trap is required for trouble free operation. If unit cooler is operated without the drain trap, warm
air with higher temperature will draw from outside to the cold room. Thus warm air will significantly reduce
the cooler capacity and may lead to ice formation in the drain pan.
If the temperature surrounding the drain line and trap is below freezing (0
o
C), it must be wrapped with a
drain line heater and insulation until out of wall of the cool room. Be sure to wrap the drain pan coupling
too.
Make sure the drain line is clear to prevent drain line plugged and overflow.
5.4
Superheat
Check suction superheat and adjust expansion valve to prevent liquid flood back to the compressor.
Recommended 5K to 20 K for suction superheat.
**Remarks: Expansion valve is not factory pre-fitted.
