York R123, Руководство по эксплуатации и техническому обслуживанию

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YORK INTERNATIONAL
148
FORM 160.55-O1 (604)
CHECKING THE REFRIGERANT CHARGE DURING UNIT SHUT DOWN
HANDLING REFRIGERANT FOR
DISMANTLING AND REPAIRS
The refrigerant charge is speci Þ ed for each chiller mod el
(See Table 4). Charge the cor rect amount of re frig er ant
and record the level in the cooler sight glass.
The re frig er ant charge should al ways be checked and
trimmed when the system is shut down.
The refrigerant charge level must be checked after the
pressure and tem per a ture has equalized between the
con dens er and cooler. This would be expected to be 4
hours or more after the com pres sor and water pumps are
stopped. The level should be at the center of the sight
glass ±1/4 inch.
Charge the refrigerant in ac cor dance with the method
shown under “Refrigerant Charging” above. The re frig -
er ant lev el should be observed and the level re cord ed
af ter initial charg ing.
If it becomes necessary to open any part of the re frig er ant
system for repairs, the fol low ing para graphs out line the
procedure for handling the re frig er ant while the sys tem
is open.
Since Re frig er ant-123 boils at 82°F under at mo spher ic
pressure, it will not be necessary to remove the re frig -
er ant if the system it to be open for only a few hours. Any
part of the system which is above the liquid level will be
ac ces si ble without disturbing the re frig er ant charge.
If the system must re main open for more than a few
hours the refrigerant should be drained and stored in
clean drums for the duration of the repair pe ri od.
If con di tions permit, the system pressure should be as
near as possible to at mo spher ic before opening the sys-
tem and the re frig er ant charge should be kept as near
as possible to 82°F to keep ei ther the re frig er ant loss or
the air intake to a min i mum. After the system has been
re-as sem bled, the air should be removed by means of
the purge unit. (See “Purging the System”.)
MEGGING THE MOTOR
While the main disconnect switch and compressor mo tor
starter are open, meg the motor as follows:
1. Using a megohm meter (megger), meg between
phas es and each phase to ground (see Fig. 65); these
readings are to be interpreted using the graph shown
in Fig. 66.
2. If readings fall below shaded area, remove ex ter nal
leads from motor and repeat test.
Motor is to be megged with the starter
at ambient temperature after 24 hours
of idle stand by.
Maintenance