Section 10 Maintenance; General Requirements; Daily Maintenance; Scheduled Maintenance - York MILLENNIUM YCAS Installation Operation & Maintenance

Maintenance

GENERAL REQUIREMENTS

The units have been designed to operate continuously
provided they are regularly maintained and operated
within the limitations given in this manual. Each unit
should be included in a routine schedule of daily mainte-
nance checks by the operator/customer, backed up by
regular service inspection and maintenance visits by a
suitably qualified Service Engineer.
It is entirely the responsibility of the owner to provide
for these regular maintenance requirements and/or en-
ter into a maintenance agreement with a YORK Inter-
national service organization to protect the operation of
the unit. If damage or a system failure occurs due to
improper maintenance during the warranty period,
YORK shall not be liable for costs incurred to return
the unit to satisfactory condition.
This maintenance section applies to
the basic unit only and may, on indi-
vidual contracts, be supplemented by
additional requirements to cover any
modifications or ancillary equipment
as applicable.
The Safety Section of this manual
should be read carefully before at-
tempting any maintenance operations
on the unit. This section should be
read in conjunction with the MBCS
Manual.

DAILY MAINTENANCE

The following maintenance checks should be carried
out on a daily basis by the operator/customer. Please
note that the units are not generally user serviceable
and no attempt should be made to rectify faults or prob-
lems found during daily checks unless competent and
equipped to do so. If in any doubt, contact your local
YORK Service Agent.
Unit Status
Press the 'STATUS' key on the keypad and ensure no
fault messages are displayed (refer to the MBCS Manual
for explanation of messages and the Trouble Shooting
section for courses of action).
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MAINTENANCE
Refrigerant Leaks
Visually check the heat exchangers, compressors and
pipework for damage and gas leaks.
Airflow Obstructions
Check the air cooled condenser coil intakes and adja-
cent areas are clear of foreign materials or obstructions
e.g. paper, leaves, etc.
Operating Conditions
Read the operating pressures and temperatures at the
control panel using the display keys and check that these
are within the operating limitations given in the MBCS
Manual.
Compressor Oil Level
Check the compressor oil level after the compressor
has been operating on 'FULL LOAD' for approximately
half an hour. The oil level should be about half way up
the upper of the two sight glasses. When the compres-
sor is operating at 'PART LOAD', the level may fall as
far as half way down the lower sight glass but should
not fall below this level. When the compressor returns
to full load the level will return to the upper sight glass.
Refrigerant Charge
When a system starts up, or sometimes after a change
of capacity, a flow of bubbles will be seen in the liquid
line sight glass. After a few minutes of stable operation,
the bubbles should clear leaving just liquid refrigerant
showing in the sight glass.

SCHEDULED MAINTENANCE

The maintenance operations detailed in the following
table should be carried out on a regular basis by a suit-
ably qualified Service Engineer. It should be noted that
the interval necessary between each 'minor' and 'ma-
jor' service can vary depending on, for instance, appli-
cation, site conditions and expected operating schedule.
Normally a 'minor' service should be carried out every
three to six months and a 'major' service once a year.
It is recommended that your local YORK Service Cen-
ter is contacted for recommendations for individual sites.
Chiller / Compressor Operating Log
A Chiller/Compressor Operating Log is supplied on the
following page for logging compressor and chiller oper-
ating data.
YORK INTERNATIONAL