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Power Connections
Check that the customer power cables are connected cor-
rectly to the terminal blocks or optional circuit breaker.
Ensure that connections of power cables within the
panels to the circuit breaker or terminal blocks are tight.
Grounding
Verify that the unit's protective ground terminal(s) are
properly connected to a suitable grounding point. Ensure
that all unit internal ground connections are tight.
Water System
Verify the chilled liquid system has been installed cor-
rectly, and has been commissioned with the correct
direction of water flow through the cooler. The inlet
should be at the refrigerant piping connection end of
the cooler. Purge air from the top of the cooler using the
plugged air vent mounted on the top of the cooler body.
Flow rates and pressure drops must be within the limits
given in the Technical Data Section. Operation outside
of these limits is undesirable and could cause damage.
If mains power must be switched OFF for extended
maintenance or an extended shutdown period, the
compressor suction, discharge and economizer service
stop valves should be closed (clockwise). If there is
a possibility of liquid freezing due to low ambient
temperatures, the coolers should be drained or power
should be applied to the chiller. This will allow the
cooler heater to protect the cooler from freezing down
to –20°F. Before placing the unit back in service, valves
should be opened and power must be switched on (if
power is removed for more than 8 hours) for at least 8
hours (24 hours if ambient temperature is below 86°F
[30°C]) before the unit is restarted.
Flow Switch
Verify a chilled water flow switch is correctly fitted in
the customer's piping on the cooler outlet, and wired
into the control panel correctly using shielded cable.
There should be a straight run of at least 5 pipe diam-
eters on either side of the flow switch. The flow switch
should be connected to terminals 2 and 13 in the panel.
Temperature Sensor(s)
Ensure the leaving liquid temperature sensor is coated
with heat conductive compound (Part No. 013-00890-
000) and is inserted to the bottom of the water outlet
JOHNSON CONTROLS
sensor well in the evaporator. This sensor is part of the
pump control freeze protection operation. It provides
some freeze protection and must always be fully inserted
in the water outlet sensor well.
Programmed Options
Verify that the options factory-programmed into the
Micro Panel are in accordance with the customer's
order requirements by pressing the OPTIONS Key on the
keypad and reading the settings from the display.
Programmed Settings
Ensure the system cutout and operational settings are in
accordance with the operating requirements by pressing
the PROGRAM key.
Date and Time
Program the date and time by first ensuring that the CLK
jumper JP2 on the chiller control board is in the ON posi-
tion. Then press the DATE/TIME key and set the date
and time. (See Page 288.)
Start/Stop Schedule
Program the daily and holiday start/stop by pressing the
SCHEDULE key. (See Page 289.)
Setpoint and Remote Offset
Set the required leaving chilled liquid temperature setpoint
and control range under the SETPOINTS Key. The chilled
liquid temperature control settings need to be set according
to the required operating conditions.
If remote temperature reset (offset) is to be used, the maxi-
mum reset required must be programmed by pressing the
SETPOINTS Key. (See Page 279.)
FIRST TIME START-UP
During the commissioning period there
should be sufficient heat load to run the
unit under stable full load operation
to enable the unit controls, and system
operation to be set up correctly, and a
commissioning log taken. Be sure that
the chiller is properly programmed and
the System Start-up Checklist (Page 188)
is completed.
FORM 201.21-NM3 (616)
5
37
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