Mk8 EGA Evo

Overview: CEMS emissions auditing and trim control
For decades, boilerhouses, manufacturing plants and other industrial environments have used EGA’s (Exhaust Gas Analyser) to monitor flue emissions to comply with environmental regulations & to reduce fuel usage & emissions. The EGA EVO can operate as a standalone independent continuous monitor, or it can feed back its readings to an Autoflame MM Boiler Controller, allowing the MM to adjust the fuel/air ratio (trim) of the burner for optimised performance.


  • Simultaneous & continuous sampling of up to 6 exhaust gases (O2, CO2, CO, NO, NO2 & SO2) at a fraction of the price of alternative systems. Use with Autoflame MM Controller or Standalone Mode.
  • Enables 3 parameter trim control in MM Controller for improved fuel efficiency and emission reduction.

With built-in CEMS Auditing software, view reports by user-definable time periods (24 hours, 2 weeks, 1 month, 2 years, etc.) based on:

  • Total weight & volumetric emissions
  • Weight/volumetric emissions per exhaust
  • Total cost of fuel

Mk8 EGA EPA Conformance

Meets all requirements set by US Environmental Protection Agency
Includes all the benefits of the Standard Mk8 EGA (CEMS Software, monitors up to 6 gases, touch screen) plus:


  • Additional back box enabling ability to self-calibrate sensors every 24 hours
  • 4 Connectors added to the bottom of the EGA., so that 4 different span gas bottles can be added for self-calibration purposes
  • Heated Sample Line to maintain Exhaust Gas temperature during sampling
  • Quick connect H.S.L. fitting on the top of the EGA


The US Environmental Protection Agency have certain requirements for monitoring boiler flue emissions. The Mk8 EGA EPA Conformance model has been specifically designed to conform to these requirements.


Enables automated cell calibrations on bottled calibration gas (4 bottles). Self-calibration process occurs once every 24 hours. During this process, the cells are each recalibrated using a zero value, and a span value. The following configuration options are available:


  • User-defined span gas configuration
  • Customisable timings for sample and purge of each span gas
  • E.G.A. can perform up to two automated cell calibrations per day. User configurable to sample to certain times of day (e.g., 9am & 9pm) or after a prescribed interval of hours.
  • Ranging of 4-20mA signal from fuel flow meter to maximise accuracy


Additionally, the EPA EGA has the following information:

  • Graph indicating remaining life and accuracy of each cell
  • On-screen indication of self-calibration stage and which bottle is used
  • Logging of cell calibration, readings, and drift over time
  • Calibration drift measured over the space of 5 calibrations. If excessive calibration drift is measured, the last valid calibration data is used


Heated Sample Line (HSL)
Heated Sample Line ensures sample gas is not diluted by water (condensate). The HSL maintains the exhaust gas temperature until the gases enter the E.G.A.


HSL temperature can be controlled to user-defined setting. The temperature is monitored to provide warning when not at the prescribed setting


The HSL operates by using a PI loop to maintain the set temperature

Mk8 EGA Evo Servicing and Calibration

The Autoflame EGA requires an annual service. During this service, the EGA is cleaned, recalibrated and inspected for faults.


EGA’s can be returned for these services to either our UK Manufacturing Headquarters, or to our partners in the USA, Midwest Combustion.
For more information, call: +44 (0) 1959 578 821


For information relating to EGA repairs within the USA, call: (620) 229 8048.

Mk8 O2 Interface

This module enables O2 trim with Mini Mk8 and Mk8 MM Controllers for limited budget applications. We generally recommend the Mk8 EGA Evo instead, as it enables a more advanced 3 parameter trim.


O2 interface setup
The default configuration for inputs and output 1 is 4-20mA, (0-10Vdc can also be used).


Inputs 2 and 3 are set to 150ºC and 20ºC as default, (4-20mA or 0-10Vdc can also be used).


Analogue Input 1 – O2 Signal Input
Analogue Input 2 – Stack Temperature Input
Analogue Input 3 – Inlet Temperature Input
Analogue Output 1 – Firing Rate Output