Johnson Controls YEWS Series, Инструкции по установке, эксплуатации и техническому обслуживанию

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8 MAINTENANCE
8.1 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
maintenance 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 enter into
a maintenance agreement with a YORK 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 individual 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 attempting any maintenance
operations on the unit.
8.2 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 problems 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 control center
operation instructions for explanation of messages and the
Trouble shooting section for courses of action).
Refrigerant charging and leaks checking
Refrigerant leaks checking
Periodic refrigerant leak checking must be part of a
comprehensive maintenance program. Leak check the
entire chiller using a calibrated electronic leak detector.
Confirm leaks with soap bubbles that are found using the
electronic leak detector.
Check refrigerant relief valve piping and tube rolled
joints as part of the comprehensive refrigerant leak
checking program.
Repair leaks before adding refrigerant.Visually check the
heat exchangers, compressors and pipework for damage
and gas leaks.
Determining correct refrigerant charge level
The refrigerant charge level is correct when the measured
evaapraror approach and discharge superheat are within
the values listed in Table 8-1.
Liquid refrigerant will be visible in the evaporator sight
glass.The refrigerant level can not be properly
determined by viewing the liquid refrigerant level in the
evaporator sight glass.
All YEWS-E units shipped From1 are charged with the
correct amount of refrigerant.Under some operating
conditions the chiller may appear to be overcharged or
undercharged with refrigerant. Consult with YORK
Factory prior to removing or adding refrigerant.
Definitions
Evaporator approach= (S.E.T)-(L.E.L.T)
Discharge superheat= (C.D.G.T)-(S.C.T)
When:
S.E.T = Saturated Evaporator Temperature
L.E.L.T =Leaving Evaporator Liquid Temperature
C.D.G.T =Compressor Dischrge Gas Temperature
S.C.T = Saturated Condensing Temperature
Refrigerant Charge
Should it become necessary to add refrigerant charge to a
YORK YEWS-E Chiller; add charge until the evaporator
NOTE
WARNING
YEWS-E Water Cooling Screw Chiller/Heat Pump
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