270NH3.MAN.REVD.062019
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10.0 Troubleshooting
The following table should give an overview of possible errors and an instruction to check and to repair them.
Error
Possible reason
Check/Repair
No sample gas flow
Filter element plugged
Filter chamber exit port plugged
Check/ replace filter element
Remove filter element and
inspect exit port. Exit port will be
located at 0° or 180° from the top,
depending on configuration
Low temperature alarm
Insufficient warm-up time
Power disconnected
Control switch defective
Ensure power has been applied
to the unit for a minimum of 15
minutes
Ensure power is supplied to the
unit. Check by measuring for AC
voltage on TB1-1 & 2
Verify by measuring for a closed
circuit between TB1-1 & 4
High oxygen readings/ low
pollutant readings
Leak
Leaking past the filter cap O-ring:
Remove filter element using the
filter change instructions. Inspect
the O-ring under the filter cap by
removing the 3 screws in the top
of the cap and removing the
aluminum section from the filter
cap plug. The O-ring under the
aluminum cap should be pliable,
undamaged, and seated in its
groove. Replace the O-ring if
necessary.
Leaking blowback solenoid valve:
Block or disconnect the blowback
supply and look for a change in
the analyzer readings.
Loose connection:
Verify all fittings are tight and leak
free
Low readings during calibration
Insufficient calibration gas flow
Ensure calibration flow is at least
110% of the sample gas flow
