H. Maintaining and Troubleshooting the AQSync
Model AQSync Air Quality Monitoring Station Manual Rev. A-1
49
H.2.3
NOx Module Troubleshooting
Use the troubleshooting tips below along with
the error byte shown in the Parameters table to
diagnose issues. Also refer to the manufacturer
information linked in Appendix 1. The error byte
codes are shown after the Troubleshooting
table.
Pump 2 is the connection for
the NOx module’s
pump. When adjusted and functioning properly,
the Cell Flow Rate will be 1400-1600 cm
3
/min)
and the Ozone Flow Rate should be 60-80
cm
3
/min
.
Table H.3. Troubleshooting the NO
2
/NO/NO
x
Module for performance problems.
Problem/Symptom
Likely Cause
Corrective Action
Instrument turns on then
powers off.
Burned out air pump.
Remove module cover and
unplug air pump. Turn
instrument on; if it remains
running, then the air pump
motor is burned out and
shorting. Replace air pump.
Cell temperature reads low
by several 10’s of degrees.
Absent or loose connection of
temperature probe cable to
circuit board.
Remove module cover and
reattach connector to circuit
board.
Readings are noisy with
standard deviations much
greater than 3 ppb using 5-
second averaging.
LED output is weak
Excessive vibration
Flow path contaminated
Remove top cover and check
LED connection to circuit
board. If photodiode voltage
is less than 0.5 V, replace
LED.
Provide additional vibration
insulation for the instrument
such as a foam pad.
Contact 2B Technologies for
instructions if contamination
is suspected.
Required calibration
parameters are outside the
adjustable range when
calibrated using a known
calibration gas.
Flow path is contaminated.
Solenoid valve is
contaminated and not opening
& closing properly.
Contact 2B Technologies for
instructions if contamination
is suspected.
Remove solenoid valve, rinse
with methanol, dry with zero
air, and replace.
