Teledyne 3000TB Instruction Manual page 72

5 Maintenance Model 3000TB
Increase flow rate and/or length or vent tubing in order to dilute of minimize
the diffusion of oxygen from the vent back to the sensor.
Problem:
Inaccurate zero operation (i.e. the user has zeroed the analyzer accidentally
on gas much higher than one would normally use for a zero gas).
Solution:
Turn the analyzer off, then back on again. Press the System key when
prompted by the analyzer "Press System for default Values". This will
return the analyzer to its default settings in calibration and zero values. Now
proceed to carefully calibrate and zero the analyzer.
5-10
Teledyne Analytical Instruments