Daikin Trailblazer AGZ226-241E - Page 125

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www.DaikinApplied.com 125 IOM 1207-6 • TRAILBLAZER
®
MODEL AGZ CHILLERS
Figure 96: Flow Switch Details
It is commended, if possible, that the ow switch be mounted
such that the electrical connection and indentation ‘mark’ are
pointed in the direction of ow as shown in Figure 97. It is
important that the ow switch be mounted so that the probe is
su󰀩ciently inserted into the uid stream. It may not be mounted
directly on top or directly on the bottom of a horizontal pipe.
Figure 97: Remote Mounting Guidelines for Flow Switch
If the ow sensor is to be mounted away from the unit, the
sensor should be mounted on the wall of the outlet pipe of
evaporator, or in a run of straight pipe that allows 5 to 10 pipe
diameters prior to the sensor and 3 to 5 pipe diameters of
straight pipe after the sensor. Flow switch is placed in outlet
pipe to reect ow leaving the barrel. If installation on the
inlet pipe is necessary, contact Chiller Technical Response
at TechResponse@DaikinApplied.com to review the jobsite
details.
NOTE: DO NOT alter or relocate factory installed ow switch.
If issues exist, contact Chiller Technical Response at
TechResponse@DaikinApplied.com.
If needed, the adapter is threaded into the pipe using pipe
sealant appropriate for the application. The ow sensor is
mounted onto the adapter using silicone grease. Carefully
apply lubricant to the inside threads and o-ring so temperature
probe does not become coated with lubricant. Torque the
adapter/sensor connection to 18.5 ft/lbs.
Wiring
Refer to wiring diagram in the unit control panel. Either AC or
DC is used to power the ow switch. The unit controller’s digital
input is a DC signal which is supplied through the switch output
of the ow switch for ow indication. It is required that the AC
and DC commons of power be separated. Contact Chiller
Technical Response for alternate wiring scenarios.
Flow Switch Setup
The ow switch comes from the factory set at a default velocity
of 300 cm/s. This value is typically well below the minimum
water ow specied for the unit’s evaporator and condenser so
eld adjustment is required for adequate low ow protection.
Table 87 are the calculated gallons per minute (gpm) for
Schedule 40 steel pipe for various uid velocities from 15 cm/s
to 60 cm/s. The ow switch has a range of adjustment from 3
cm/s to 300 cm/s.
Step 1: Adjust ow through the evaporator to the minimum
desired operating gpm. Maintain this ow throughout the setup
procedure.
Step 2: Once steady state minimum desired operating ow is
obtained, perform the ‘Teach’ function on the ow switch. The
‘Teach’ function is initiated by holding down the minus ‘-’ button
on the face of the ow switch for 15 seconds. During this 15
second period, LEDs ‘0’ and ‘9’ will be lit green. Once the
‘Teach’ function is completed, the outer LEDs will ash green
as shown in Figure 98.
Figure 98: Automatic Teach of Setpoint
Step 3: After the ‘Teach’ function is completed and the outer
LEDs ashed, the ow switch will indicate a new set point
based upon the current ow which should still be at the steady
state minimum desired operating ow. Figure 99 shows a
typical display for this condition. All LEDs to the left of the
SP LED are lit green. The SP LED is lit RED (or may toggle
amber) which indicates that the ow switch is OPEN. Typically,
an increase in uid ow is between 15% to 30% above the
‘Teach’ function ow is required for the SP LED to turn AMBER
and the ow switch to CLOSE indicating acceptable ow.