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Would like info on Combustion Analyzers, gases measured, units, functions

njwebdevguy Member Posts: 33

Would some of you folks who have Combustion Analyzers be willing to post what gases they measure, what the range of values they measure, and what functions they execute with the info they collect. Also, would it be possible to leave a combustion analyzer in place as a permanent addition to a heating setup.

I'm gathering they have a probe which is inserted inline in the exhaust gas flow, (chimney/flue) etc. Are there any other points at which the analyzer does its analysis? (do they analyze air intake?)

I'm basically wondering whether its possible to build one and how much it would cost.

How are they calibrated? Do you use reference samples?


  • njwebdevguy
    njwebdevguy Member Posts: 33
    What's in a Combustion Analyzer? What does it measure?

    Would it be enough to measure O2, CO2, CO, and  (which? all?) of the following..

    "Natural Gas"

    LPG and propane





    Then what kind of number crunching/display needs to be done?

    Thank you!
  • Tim McElwain
    Tim McElwain Member Posts: 4,628
    edited November 2011
    If you go online

    to the various websites of the folks who make these you will get all the info you are asking for.

    Bacharach, Testo, Wohler, UEI, E Instruments, TSI are just some of the manufacturers.

    These all use a probe which must be placed in the flue connection  of the appliances. The probes include a thermocouple type sensor inside the probe for measuring flue gas temp. 

    The testers can be set for measuring

    Natural gas (methane)

    Propane (LP)


    #2 oil

    #6 oil

    These testers are designed to measure flue gases and analyze them and give readings such as


    Flue Temp,


    Carbon Monoxide diluted

    Carbon Monoxide air free (actual CO)

    CO2 which is actually not directly measured with a sensor but is a calculated reading done by the meter electronics.

    Efficiency same thing it is a calculated reading

    Draft in inches water column typically

    Some testers also measure nitrous oxide

    There are some very expensive instruments that are also available which are typically used on some commercial and industrial applications.
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