Fieldpiece AOX2
Combustion Check Accessory Head

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Fieldpiece AOX2 Shown
Product Information
Manual 741 KB PDF Datasheet
PDF HelpPDF Help
  • Measures %O2 and Flue Gas
  • Calculates %O2
  • Natural Gas, Oil #2
  • Works with any expandable Fieldpiece meter or any meter with mVDC ranges using our detachable leads
  • Measurements for most common fuel types - Gas and Oil
  • Simple operation
  • Gives you the tests you're looking for to get the job done quickly and efficiently
  • Doesn't include a lot of extra tests, calculations and buttons you don't need and that get in the way
  • Fraction of the cost of full-function combustion analyzers
  • APO (Auto power off)
  • Thermocouple calibration pot on front-face of meter for quick adjustments
  • Quick and easy filter replacement on included AOXP2 hand pump

The Fieldpiece AOX2 Combustion Check Accessory measures percent oxygen (%O2) and flue temperature and calculates percent carbon dioxide (%CO2). The Fieldpiece AOX-2 is an affordable alternative to full-function combustion analyzers. The Fieldpiece AOX2 is designed for techs who want to do everyday combustion testing and tuning, without paying for all of the costly extras found on combustion analyzers - extras they don't need or care about.

The Fieldpiece AOX/2 Attachable Combustion Check allows you to easily calibrate combustion equipment such as boilers or furnaces to the manufacturer’s specified % CO2, or % O2. Tuning the CO2, O2 stack temperature and temperature rise to match the appliance manufacturer’s specifications will increase efficiency and help maximize performance and life expectancy of the equipment. Tuning typically involves adjusting the air/fuel ratio.

% CO2
Working range (percent) 0 to 25%
Resolution 0.1% CO2
Accuracy 0 to 25% ±0.3% (calculated)
% O2
Working range (percent) 0 to 25%
Maximum Overload 30% O2
Resolution 0.1% O2
Accuracy 0 to 25% ±0.3% O2 (@72°F (22.2°C) 20.9% O2 ambient)
Stabilization time under 2 minutes
Range (temperature) -58°F to 1000°F; -50°C to 538°C
Resolution 0.1°F/0.1°C
System Accuracy ±0.6% + 3°F (1.7°C) after field calibration)
Technical Specifications
Sensor calibration Factory calibrated on 205ppm
Long term drift <5% / year (depending on use)
Battery 9V
Battery life Approx.150 hrs typical (Alkaline)
Auto power off (APO) 15 minutes
Ordering Information
Model Description Buy Online Price
AOX2  Fieldpiece AOX2 Combustion Check Accessory Head Buy Now Sale $168.80
(Reg. $211.00)
Included Accessories
  • 1 - Calibration screwdriver
  • 1 - 9-Volt battery (installed)
  • 1 - Operator’s manual
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