IOM 1206-13 • TRAILBLAZER
®
MODEL AGZ CHILLERS
104 www.DaikinApplied.com
Startup and Shutdown Procedures
• Verify remote start / stop or time clock (if installed) has
requested the chiller to start.
• Set the chilled water setpoint to the required temperature.
(The system water temperature must be greater than the
total of the leaving water temperature setpoint plus one-
half the control band plus the startup delta-T before the
MicroTech
®
III controller will stage on cooling.)
• Set the Evap Delta T based on a percent of unit nominal
flow indicated in
and the Start Delta T as a
starting point. Delta-T=Tons x 24 / gpm
• Check the controller setpoints to be sure that factory
defaults are appropriate.
• Put both pumpdown switches (PS1 and PS2) to the ON
position.
• Put system switch (S1) to ON position.
Table 86: Pumpdown and System Switch Positions
Switch
Switch Position
ON
OFF
PS1, PS2,
Pumpdown Switches
Circuits will operate
in the normal,
automatic mode
Circuit will go
through the normal
pumpdown cycle and
shut off.
S1, System Switch
Unit will operate in
the normal automatic
mode
Unit will shut off
immediately without
pumping down
(emergency stop)
Post Startup
After the chiller has been operating for a period of time and has
become stable, check the following:
• Compressor oil level.
•
Refrigerant sight glass for flashing.
• Rotation of condenser fans.
• Complete the “Equipment Warranty Registration Form,”
found at the end of this manual, within 10 days of start-
up in order to comply with the terms of Daikin Limited
Product Warranty.
Shutdown
Temporary Shutdown
1. Put both circuit switches to the OFF position (Pumpdown
and Stop).
2. After compressors have stopped, put System Switch (S1)
to OFF (emergency stop).
3.
Turn off chilled water pump. Chilled water pump to
operate while compressors are pumping down.
4. To start the chiller after a temporary shutdown, follow the
startup instructions.
Extended Shutdown
1. Front seat both condenser liquid line service valves.
2. Put both circuit switches to the OFF position (Pumpdown
and Stop position).
3. After the compressors have stopped, put System Switch
(S1) to the OFF position (emergency stop).
4. Front seat both refrigerant circuit discharge valves (if
applicable).
5. If chilled water system is not drained, maintain power to
the evaporator heater to prevent freezing. Maintain heat
tracing on the chilled water lines.
6. Drain evaporator and water piping to prevent freezing.
7. If electrical power to the unit is on, the compressor
crankcase heaters will keep the liquid refrigerant out of
the compressor oil. This will minimize startup time when
putting the unit back into service. The evaporator heater
will be able to function.
8.
If electrical power is off, make provisions to power the
evaporator heater (if chilled water system is not drained
or is filled with suitable glycol). Tag all opened electrical
disconnect switches to warn against startup before the
refrigerant valves are in the correct operating position.
To start the chiller after an extended shutdown, follow the pre-
startup and startup instructions.
Flow Switch Installation and Calibration
A thermal dispersion flow switch uses heat to determine
flow and therefore must be calibrated during system startup.
A thermal dispersion flow switch can be an acceptable
replacement for paddle type flow switches and differential
pressure switches but care must be taken regarding wiring.
The thermal dispersion flow switch supplied by Daikin Applied,
shown in
, comes as a 2 part unit consisting of a flow
switch and an adapter labeled E40242 by the supplier.
Figure 78: Thermal Dispersion Flow Switch and Adapter
IMPORTANT
: Flow switch
MUST be calibrated before
chiller operation. Failure to
properly calibrate the switch
may result in severe chiller
damage and/or void warranty.
