Daikin Navigator WWV - Chilled Water Pump Operation; Compressor VFD Inspection Points; Planned Maintenance Schedule

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IOM 1264-4
WWW.DAIKINAPPLIED.COM
MAINTENANCE
Do not use the sight glass on the EXV body for refrigerant
charging. Its purpose is to view the position of the valve.
Pump Operation
It is highly recommended that the chiller unit control the chilled
water pump(s). The integral chiller control system has the
capability to selectively start pump A or B or automatically
alternate pump selection at each start and also has pump
standby operation capability.
Failure to have the chiller control the pumps may cause the
following problems:
1. If any device, other than the chiller, should try to start
the chiller without rst starting the pumps, the chiller will
lock out on the no-ow alarm and require a manual reset
to restart. This can be disruptive to the normal cooling
process.
2. In areas where freeze-up is a concern, the chiller control
senses the chilled water temperature. It also signals the
chilled water pump to start to providing ow through the
evaporator and additional protection against evaporator
and outside pipe freeze-up. Other pump starting methods
will not automatically provide this protection. Note: the
owner/operator must be aware that when the water
temperature falls below freezing temperatures it is
imperative NOT to stop the pump(s) as immediate freeze-
up can occur.
This method of freeze protection is only e󰀨ective as long
as the facility and the chiller have power. The only positive
freeze protection during power failures is to drain the
evaporator and blow out each tube or add the appropriate
concentration of glycol to the system.
Compressor VFD
Table 33: Compressor VFD Inspection Areas
Inspection
Area
Inspection Points Corrective Action
General
Inspect equipment for dis-
coloration from overheat-
ing or deterioration.
Replace damaged equip-
ment as required.
Inspect for dirt, foreign
particles, or dust collec-
tion on components
Inspect door seal if so
equipped. Use dry air to
clear foreign matter.
Conductors
and Wiring
Inspect wiring and con-
nections for discoloration,
damage or heat stress.
Repair or replace dam-
aged wire.
Terminals
Inspect terminals for
loose, stripped, or dam-
aged connections.
Tighten loose screws and
replace damaged screws
or terminals.
Relays and
Contactors
Inspect contactors and
relays for excessive noise
during operation.
Check coil voltage for
over or under voltage
condition.
Inspect coils for signs of
overheating such as melt-
ed or cracked insulation.
Replace damaged remov-
able relays, contactors or
circuit board.
Figure 44: Planned Maintenance Schedule
Operation Weekly
Monthly
(Note 1)
Annual
(Note 2)
General
Complete unit log and review
(Note 3)
X
Inspect unit for loose or dam-
aged components and visible
leaks
X
Inspect thermal insulation for
integrity
X
Clean and paint as required X
Electrical ( * including the VFDs)
Sequence test controls * X
Check contactors for pitting,
replace as required *
X
Check terminals for tightness,
tighten as necessary (including
compressor) *
X
Clean control panel interior * X
Clean control box fan lter * X
Visually inspect components for
signs of overheating (including
compressor) *
X
Refrigeration/Lubricant
Leak test X
Check liquid line sight glasses
for clear ow
X
Check oil sight glass for correct
level (lubricant charge)
X
Perform compressor vibration
test (optional)
X
Perform oil analysis test on
compressor oil
X
Evaporator and Condenser (water-cooled)
Conrm correct water ow and
pressure drop
X
Conrm appropriate water
treatment
X
Clean and Leak Test tubes X
Clean Flow Sensor X
NOTE: 1 Monthly operations include all weekly operations.
2 Annual (or spring startup) operations include all
weekly and monthly operations.
3 Log readings can be taken daily for a higher level of
unit observation.
4 The weekly fan lter cleaning schedule can be
modied to meet job conditions. It is important that the
lter allows full air ow.