Three Gas Analyzer


Product Details


Video demonstrations can be found on our website, including both calibrating O2 sensors and calibrating CO2 sensors.

Gas tank attachment tutorial:

For more please see the Calibration Instructions.

For hardware versions 004 and older, see our legacy calibration instructions.

There are common, everyday sources of ethylene that can be picked up on by the sensors in your Felix Gas Analyzers. Common sources of ethylene include smoke or exhaust. Furthermore, the ethylene sensors inside of the Felix Gas Analyzers are also sensitive to various volatile organic compounds (VOCs). Various cleaning agents are often a source of VOC readings. If you are inside, it is not uncommon for the ethylene sensors to report readings between 0-0.5ppm of ethylene. If you are outside, drawing clean ambient air (away from traffic, smoke, or other sources of exhaust) it is more typical to see 0.0 ppm readings for ethylene.

The 16GB card provided with the F-9xx gas analyzers technically has indefinite storage capacity as the files can be moved off the card to reopen storage space. However, without moving any files off the card, it can hold up to ~60 million measurements from a F-9xx analyzer. If the instrument is saving data every minute that equates to ~40,000 days of measurement before the SD card is full. 

  1. Open up the desired manual in a browser window 
  2. Click ‘Accessibility Mode’ 
  3. Select the download icon. The manual will download as a pdf. 

I don’t feel that my F-9xx Gas Analyzer is reading accurately, what should I do? 

When communicating with support it is helpful to provide: 

  1. Serial number and firmware version on the instrument 
  2. Send the sensor parameter file (.config file) found on the SD card by doing the following: 
  3. Navigate to setup>factory setup 
  4. Select ‘backup’. The instrument will store a backup file of the current configuration file.  
  5. Send this config file with the day’s date to 


If your analyzer is less than three months old, see the two options below: 

  1. Try restoring the factory defaults on the device  
  2. Navigate to setup>factory setup 
  3. Select ‘restore’ and restore the parameter file containing the calibration set at the manufacturers facility 
  4. Perform a baseline calibration on the sensors 

Perform a set zero calibration on the sensors using the external conditioning chamber filled with potassium permanganate for the ethylene sensor and the external conditioning chamber filled with soda lime for the CO2 sensor. Use the O2 calibration in air menu option to calibrate the O2 sensor using ambient air. Only use the O2 set zero setting if you are using 100% nitrogen gas.  

Please see the user manual for more details.  

If your analyzer is over three months old, see options below: 

If your instrument is over three months of age, inaccurate sensor readings could indicate a need for calibration. You can try a baseline calibration (or set zero) of the sensors first and if this does not bring the readings into spec, then perform a full calibration.  

Please see ‘How Do I Calibrate the Instrument?’ FAQ for more details.  

The sensors within your gas analyzer are calibrated with a two-point calibration, with verification at a third point using certified standard gases. These three points include: 1. A set zero or baseline calibration for the sensor; 2. a span or gain calibration of the sensor; and 3. verification with a third standard gas concentration between the baseline and gain points. 

The sensor response will naturally drift over time. To make sure you are getting accurate readings it is essential that you keep up with the calibration schedule of the instrument. 

Set zero or baseline calibration

The set zero calibration should be completed once a week. The gas analyzers are supplied with external conditioning chambers and the proper solids to perform this process. No standard gases are required for this, please see your corresponding user manual for more details. 

Span or gain calibration

A span calibration should always be preceded by setting the baseline response of the sensor. If performing a span calibration, please review the ‘How do I calibrate the instrument?’ FAQ. 

  • Ethylene sensor - should be performed every 3 months
  • CO2 sensor - should be performed annually
  • O2 sensor - should be performed biannually 

What standard gases do I need to calibrate my instrument on my own?

Learn more in our documentation.

  • Navigate to the manual you wish to translate (available in our support section).
  • Once the manual is open, select the contextal menu by selecting the "..." option in the upper-right hand corner of your screen.
  • Select the translate option (as shown above).
  • Select your preferred language. Select translate.

Note: Due to limitations of Microsoft Translate, manuals greater than 50 pages in length currently do not support dynamic translation.

Yes! Due to the scarcity of the C2H4 sensors used in some early models, we are no longer able to replace these sensor.

To know if your F-950 is impacted please refer to the serial number on the back and note the middle three digits, this is the version number of the instrument you have.

The versions that are impacted are 001, 002, 003. They were produced between 2014 and 2016.

An example: 950-001-14xxx

If the F-950 sits for an extended period of time without battery charge to the control board, the ethylene sensor can begin to consume itself and will decrease in sensitivity.  When charged batteries are replaced in the unit it typically takes a few days for calibrations to be restored to all sensors (48 hours to stabilize).  In the case of the ethylene electrochemical sensor, the calibration parameters may no longer be valid if the device was without charge for more than a week.  This will require re-calibration with standard gases.

The ethylene zero should be set daily, unless verified to be reading properly with potassium permanganate (KMnO4).  In this case, the set zero procedure does not need to be carried out. But, it the C2H4 zero should be re-checked the next day the F-950 is used.  


Climacteric fruits refer to fruits that have high respiration rate during the fruit's ripening. During the ripening process of climacteric fruits, the production of a phytohormone, ethylene, dramatically increases up to 1000-fold of the basal ethylene level.  Climacteric fruits are ones that are able to ripen after being picked. An example of climacteric fruit is bananas; they are picked and shipped green and then ripen at a later time (often in the store or home).  Climacteric fruits include, but are not limited to, apples, apricots, avocados, bananas, cantaloupes, figs, guavas, kiwis, mangoes, nectarines, peaches, pears, persimmons, plums, and tomatoes.  [Source:]