HSO 2024 to HSO 2035 Installation, Operation and Maintenance Manual
Issue 1.2 : 03/10
Publication 2-119
Page 53 of 94
During the running-in period, as oil is distributed throughout the system, it
may be necessary to add extra oil from time to time until the overall oil
content has stabilised. Afterwards, it should only be necessary to replace
the small quantity of oil lost during maintenance exercises, for example,
changing the oil filter element.
Applicable to plants charged with ammonia (R717),
not
applicable to
other refrigerants.
Unless the system is fitted with an oil still which automatically returns oil
to the separator/reservoir, it is usually necessary to manually drain oil
from vessels in the LP side of the system (suction separator, flooded
evaporator or plate heat exchanger). If there is very little oil to drain, this
period can be extended.
11.7.
Checking for Leaks
Check the plant daily during the first week or two of operation for leakage
of refrigerant or oil; thereafter check for leaks weekly.
11.8.
Compressor Drive Motor Coupling
After the first 12 hours of compressor operation, stop the plant and
remove the guard from the drive coupling. Remove the coupling
membrane/spacer assembly.
Check the tightness of the
Taper Lock bush grubscrews securing the
compressor half-coupling, check the half-couplings have not slackened-
off their shafts.
Check and record the distance between shaft ends (DBSE) and the drive
alignment. The half-couplings should be aligned within 0.125 mm when
using dial test indicators on each face and around the circumference.
Refit the membrane/spacer assembly and the coupling guard.
Recheck and record the DBSE and drive alignment after approximately
the first 200 operating hours.
11.9.
Compressor and Drive Motor Holding-Down Bolts
After approximately the first 200 compressor operating hours, check the
tightness of the nuts securing the compressor and motor holding-down
bolts.
