IM-1125-13 • REBEL ROOFTOPS
88
www.DaikinApplied.com
Optional Outdoor Air Monitor
Table 36: General Troubleshooting
Problem
Possible Cause
Remedy
No LCD display indication and the green Transmitter
Status LED (D3) on the main circuit board is not
illuminated .
Power switch not in the "ON" position.
Move the power switch to the "ON" position.
Improper supply voltage to the power input terminal
block.
Ensure that 24VAC power is connected to L1 and L2
of the POWER terminal block and that the voltage
with the power switch in the "ON" position is between
22.8 and 26.4 VAC.
Blown fuse.
Check power wiring. Ensure that multiple devices
wired on a single transformer are wired "in-phase".
Replace fuse only with a 1.5 amp, fast-acting fuse
after the problem has been identified and corrected.
No LCD display indication and the green Transmitter
Status LED (D3) on the main circuit board is flashing. LCD contrast too low.
Turn “Contrast” potentiometer on the main circuit
board "clockwise".
The LCD display is scrambled or there is no LCD
display indication after touching the switches, LCD
display or circuit board.
Static electricity.
Touch an earth-grounded object, such as a duct, to
discharge static electricity then reset the power. Avoid
direct contact with the LCD display or circuit board.
The LCD display indicates "No Probes".
The power switch on the transmitter was moved to
the "ON" position before the sensor probes were
connected.
Reset 24VAC power by moving the power switch from
the "ON" to "OFF" position and then back to the "ON"
position .
The LCD display indicates "DiffSensor Type".
Sensor probes have been mismatched.
Transmitters must have the same sensor type
connected (GP1, GF1 or GB1 sensor probes).
The LCD display indicates "Too Many Sensors".
A probe with 5 or more sensors has been connected
to a 'Type B' transmitter with 4 receptacles.
Probes with 5 or more sensors are shipped with and
require a 'Type A' transmitter with 2 receptacles.
The last digit of the flow rate unit is displayed as a
lower case letter. (When the Field Calibration Wizard
is engaged, the last character of the flow rate units is
displayed as an upper case letter.
The sensor detection system has detected one or
more malfunctioning or missing sensors.
Check sensor probe cable connections. If sensor
probe connections look OK and match the number of
sensor probes indicated on each probe’s hang tag.
A probe with 5 or more sensors has been connected
to a 'Type B' transmitter with 4 receptacles.
Probes with 5 or more sensors are shipped with and
require a 'Type A' transmitter with 2 receptacles.
The green Transmitter Status LED (D3) on the main
circuit board is "ON" but not flashing.
The microprocessor is not running.
Reset 24VAC power by moving the power switch from
the "ON" to "OFF" position and then back to the "ON"
position .
The green Transmitter Status LED (D3) on the main
circuit board is flashing at 1-second intervals.
No problem, normal operation.
No remedy required.
The green Transmitter Status LED (D3) on the main
circuit board is flashing at 2-second intervals.
The sensor detection system has detected one or
more malfunctioning or missing sensors.
Check sensor probe cable connections. If sensor
probe connections look OK and match the number of
sensor probes indicated on each probe's hang tag.
A probe with 5 or more sensors has been connected
to a 'Type B' transmitter with 4 receptacles.
Probes with 5 or more sensors are shipped with and
require a 'Type A' transmitter with 2 receptacles.
The transmitter indicates airflow when the HVAC
system is not operating.
Sensors are sensitive and can measure very low air
velocities. If a reading is indicated, there is airflow
present where the airflow measuring station is
located.
Do not attempt to adjust zero ("offset"). Doing so will
result in an error in airflow measurement. The Low
Limit airflow cutoff value can be set to force the output
signal to zero.
No output signal can be measured at the OUTPUT
terminal block of the transmitter.
Output card is not securely mounted on main circuit
board .
Turn the transmitter power "OFF", and then press the
output card firmly onto main circuit board. Turn the
transmitter power back "ON".
Blown output fuse (output 1 and output 2 are fused
and protected independently on the transmitter).
Make sure that power has not been connected to
the output terminal block. Correct the problem and
replace with 0.125 amp, fast acting fuse only.
Make sure that the host control system is not
configured for a 2-wire device (no excitation voltage
should be present on the signals from the host
controls). Correct the problem and replace with 0.125
amp, fast acting fuse only.
The Low Limit airflow cutoff value is above the actual
airflow reading.
Decrease the Low Limit airflow cutoff value in the
Setup menu until it is below the actual airflow reading.
The output signal on the transmitter fluctuates while
the flow and/or temperature readings on the LCD are
steady .
Electrical interference from other devices is creating
noise in the signal wires to the host control system.
The output signal wiring must be shielded. Individually
ground one or more of the following points: the signal
wire shield at host controls; signal wire shield at the
transmitter, or L2 of the power terminal block of the
transmitter .
The LCD display does not match the readings
indicated by the host control system.
The scaling in the host control system is incorrect.
Compare the current configuration of the transmitter
with that of the host control system. Compare the
minimum and full scale settings for each output by
navigating through the Setup menu.
