Supply Voltage; Preparation - Power On; Switch Settings; Compressor Heaters - York YCAL0019 Installation, Operation And Maintenance Manual

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SECTION 6 – COMMISSIONING

Supply Voltage

Verify that the site voltage supply corresponds to the
unit requirement and is within the limits given in the
Technical Data Section.
PREPARATION – POWER ON
Perform the commissioning using the
detailed checks outlined in the Equip-
ment Start-Up Check List as the com-
missioning procedure is carried out.
Apply power to the chiller. Turn on the option panel
circuit breaker if supplied.
The machine is now live!

Switch Settings

Assure the chiller OFF/ON Unit Switch at the bottom
of the keypad is OFF. Place the optional circuit break-
er handle on the panel door to ON. The customer's dis-
connection devices can now be set to ON.
Verify the control panel display is illuminated. Assure
the system switches under the SYSTEM SWITCHES
key are in the OFF position.

Compressor Heaters

Verify the compressor heaters are energized. If the
ambient temperature is above 96 °F (36 °C) the com-
pressor heaters must be ON for at least 8 hours before
start-up to ensure all refrigerant liquid is driven out of
the compressor and the oil. If the ambient temperature
is below 86 °F (30 °C), allow 24 hours.
148

Water System

Verify the chilled liquid system has been installed cor-
rectly, and has been commissioned with the correct di-
rection 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 com-
pressor suction, discharge and economizer service stop
valves should be closed (clockwise). If there is a pos-
sibility of liquid freezing due to low ambient tempera-
tures, 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. Be-
fore 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 di-
ameters on either side of the flow switch. The flow
switch should be connected to terminals 13 and 14 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
sensor well in the cooler. This sensor also provides
some freeze protection and must always be fully in-
serted in the water outlet sensor well.
FORM 150.67-NM1
ISSUE DATE: 4/28/2017
JOHNSON CONTROLS

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