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Fieldpiece Instruments - SOX3 - Combchk W/Autopump

Item: sox3

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About This Product

Product Info


The new SOX3 Combustion Check meter does the same measurements and calculations as the SOX2 (measures % O2 and flue temperature, % CO2, and % EA for oil, natural gas and propane). Plus it calculates combustion efficiency, has an automatic electric pump, has a custom fuel input to work on any non-conventional furnace, AND has a field-replaceable oxygen sensor so techs never lose their tools for mandatory calibrations.The SOX3 Combustion Check is a great tool to easily tune furnaces when a full combustion analysis isn't necessary. Designed specifically for HVACR pros, the SOX3 provides all the essential measurements needed to tune most combustion equipment. It directly measures %O2 and flue temperature, and calculates %CO2, %Excess Air, and combustion efficiency.
Like all Fieldpiece products, the SOX3 Combustion Check Tool was designed to help HVACR professionals do more with their tools. From custom fuels to field-replaceable oxygen sensors, the SOX3 can be trusted to measure up for any furnace tuning job.
  • Automatic Electric Pump with Pause - Pump works automatically so there's no hand pumping, and techs can pause the pump at any time to save battery life
  • Field-replaceable Oxygen Sensor - The SOX3 Oxygen Sensor indicators tells techs when a new sensor is needed. With calibration data stored on the sensor, it can be swapped out in seconds, so there's never a need to send your instrument in for calibration.
  • Hands-free Testing - The threaded R-cone holds the barrel firmly in the flue, and the strong magnet on the back of the SOX3 holds the instrument firmly to the side of the flue, while the internal electric pump does all the work. Techs simply view the results on the triple line display.
  • Combustion Efficiency - Quickly calculated and displayed on the screen, the SOX3's combustion efficiency calculation is great measurement to help determine the health of a furnace.
  • Custom Fuels - Not only does the SOX3 test Natural Gas, Oil #2, and Propane, but it can be quickly, and easily programmed to test any type of fuel. So non-conventional furnaces are just as easy to tune and conventional furnace
  • Combustion Check - SOX3
  • Barrel and Thermocouple Handle - RSOX3
  • Threaded Barrel Lock - RCONE1
  • Filter accessory kit - RAOX9
  • Padded, Blow-molded Case
Warning: this product contains a chemical known to the State of California to cause cancer.


Weight4.85 Pounds (lbs)
Width17 Inches (In)
Height3 Inches (In)
Country of OriginTWN
Length16 Inches (In)
AccuracyStated accuracy at 23°C±5°C,
Display Options4 digit liquid crystal display(LCD) with maximum reading of 9999.
FeaturesProvides quick combustion checks for comparison with manufacturer specifications. Set up to work with various fuel types and is customizable. Choose from four display modes: hold, MAX, MIN or real time. Displays percentage O2, CO2, efficiency, excess air
IncludesProduct Only
Operating Temperature Range32°F to 122°F (0°C to 50°C)
Prop 65Yes
Warranty OfferedYes


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