G. Measuring
This chapter describes the measuring tasks that can be carried out with the product.
Familiarity with the contents of the chapter
Operation (see p. 16) is assumed.
G.1 Preparing measurements
G.1.1 Zeroing phases
Measuring the combustion air temperature
If no combustion air temperature probe is connected, the temperature measured by the
thermocouple of the flue gas probe during the zeroing phase is used as the combustion
air temperature. All dependent parameters are calculated by this value. This method of
measuring combustion air temperature is sufficient for systems dependent on ambient
air. However, the flue gas probe must be near the intake duct of the burner during the
zeroing phase.
If a combustion air temperature probe is connected, the combustion air temperature is
measured continuously via this probe.
Gas zeroing
The first time a gas measuring function is called up after the instrument has been
switched on, the measuring cells are zeroed.
testo 330-1, -3 / testo 330-1LL: The flue gas probe must be in the open air during
the zeroing phase!
The “Gas zeroing, probe in flue (0440 3331)” option is available as an option for the
testo 330-3.
testo 330-2 / testo 330-2LL: The flue gas probe can be in the flue pipe even during
the zeroing phase, if a separate AT probe is attached.
Draught/pressure zeroing
The pressure sensors are zeroed when a pressure measuring function is called up.
testo 330-1, -2 / testo 330-1LL: The flue gas probe must be in the open air during
the zeroing phase/the instrument must not be pressurised during zeroing! The
“Draught zeroing, probe in flue (0440 3330)” option is available as an option for the
testo 330-2.
testo 330-3 / testo 330-2LL: The flue gas probe can be in the flue pipe even during
the zeroing phase, if a separate AT probe is attached.
G. Measuring
G.1 Preparing measurements
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