Daikin Pathfinder AWV Installation, Operation And Maintenance Manual page 90

Step 1: Adjust flow through the evaporator to the minimum
desired operating gpm. Maintain this flow throughout the setup
procedure.
Step 2: Once steady state minimum desired operating flow is
obtained, perform the 'Teach' function on the flow switch. The
'Teach' function is initiated by holding down the minus '-' button
on the face of the flow 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 flash green
as shown in Figure 84.
Figure 84: Automatic Teach of Set point
Step 3: After the 'Teach' function is completed and the outer
LEDs flashed, the flow switch will indicate a new set point
based upon the current flow which should still be at the steady
state minimum desired operating flow.
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 flow switch is OPEN. Typically,
an increase in fluid flow is between 15% to 30% above the
'Teach' function flow is required for the SP LED to turn AMBER
and the flow switch to CLOSE indicating acceptable flow.
Figure 85: Teach Adjustment Complete
In Step 3, the 'Teach' function re-adjusted the flow switch set
point (SP) while flow was at the minimum desired operating
flow. The chiller will not operate at this flow because the
flow switch is OPEN after performing the 'Teach' function.
The benefit of the 'Teach' function is to quickly set the set
point within the desired operating range. Additional 'manual'
adjustment of set point is required in order to allow for chiller
operation at this minimum flow. The '+' and '-' buttons on the
face of the flow switch allow for the manual adjustment of the
SP. Pressing the '+' button reduces the flow set point while
pressing the '-' button increases the flow set point. Each button
press, '+' or '-', changes the flow set point by 2.5 cm/s.
Step 4: Press the '+' button until LED '9' begins to flash, as
shown in Figure 86. Opening of flow switch should now occur
at approximately 80% to 90% of minimum flow.
IOM 1242-8 • PATHFINDER
Figure 85 shows a
MODEL AWV CHILLERS
®
Figure 86: Upper Range of Minimum Flow
by pressing both the '+' and '-' buttons simultaneously for 10
seconds. The indication goes out momentarily indicating the
unit is locked. To unlock, the same procedure is performed to
toggle to unlocked.
NOTE: 1. The LED window display on flow switch represents
a velocity range of 50 cm/s. The window centers on
the set point (SP). For example, if the SP was set to
200 cm/s, then the LED labeled '0' would represent
a velocity of 180 cm/s when lit and the LED labeled 9
would represent a velocity of 230 cm/s when lit.
2. Each LED represents 5 cm/s, or two presses of the
'+' or '-' buttons.
3. When power is initially applied to the flow switch,
all green LEDs light and go out step by step. During
this time, the output is closed. The unit is in the
operating mode.
4. When making manual adjustments to the set point
(SP), if no button is pressed for 2 seconds, the unit
returns to the operating mode with the newly set
value.
Flow below display range: The SP LED will be lit red and
the leftmost LED will be flashing green. For example, if the SP
was set to 200 cm/s, the flashing labeled '0' would indicate that
the flow was below 180 cm/s. This would be shown if no flow
through chiller or lowered than desired flow.
Figure 87: Display for Flow Below Range
flashing LED labeled '9' would indicate that the flow was above
230 cm/s. This may be a normal display depending on range
by which flow varies through chiller.
Figure 88: Display for Flow Above Range
90
Startup and Shutdown
Step 5: Once
the SP is set, it
is recommended
that the sensor
be locked to
avoid inadvertent
readjustment. This
can be performed
Flow above display
range: The SP LED will
be lit amber, all LEDs to
the left and right of the
SP LED with be green
with the rightmost LED
flashing green. For
example, if the SP was
set to 200 cm/s, the
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