Desert Aire SelectAire Plus SP Series, Инструкция по установке и эксплуатации

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Desert Aire - SP Manual
Selection of quality components, quality procedures, and full testing help to ensure the sealed system failures
are minimized wherever possible. Nonetheless, the mechanical nature of many components creates some
unforeseen wear and failure in certain instances. Some units may need service at a point in the life of the
product that requires opening of the hermetic refrigeration system. Special care must be taken to ensure that
the system is returned to service without any contamination.
Whenever servicing Desert Aire equipment, observe the following:
• Use only equipment rated for the pressures and the refrigerant being serviced.
• Use only equipment dedicated to service of the refrigerant in the system. Do not use equipment to
service multiple refrigerant types.
• Purge all hoses and equipment of non-condensable gasses before connecting to the sealed
system.
• Use only original equipment parts or factory approved equivalent for servicing.
• Use only refrigerant system oil.
• Minimize the time the system is open to atmosphere while servicing. Cap all connections when
there is no active service work on the system. This is particularly important with units that contain
POE oils as moisture will be absorbed quickly and cannot be removed with a vacuum.
• Never open the system while under a vacuum. Should the system require opening to repair a leak
or other service when in a vacuum, fill with dry nitrogen to atmospheric pressure before opening.
• Have a Schrader core replacement tool available when servicing the refrigeration system. Although
rare, defective or damaged Schrader valve cores can contribute to refrigerant loss.
• Charge systems only by weight after servicing. Review the rating plate and any field charge labels.
• When servicing, additional liquid line filter dryers and suction filters may be required. This does not
apply to installation of remote condensers.
• Charge refrigerant blends, including R-410A and R-407C, with liquid only. Charging should be
done into the high side of the system whenever possible. Refer to section 5.6 for additional
procedures related to charging.
Note that the superheat should be stable and within 7 degrees. The temperature and relative humidity listed
in Figure 38 is the Return Air. Minimum value for superheat at compressor in all modes:
30.0 - 40.0
40.1 - 50.0
50.1 - 60.0
60.1 - 70.0
70.1 - 80.0
60.0 - 65.0
12
13
13
14
14
65.1 - 70.0
13
14
14
15
15
70.1 - 75.0
14
15
15
15
16
75.1 - 80.0
15
15
16
16
18
80.1 - 85.0
15
16
18
18
19
85.1 - 90.0
16
18
18
19
20
Figure 38 – Superheat Minimum Values Chart