Exhaust Gas Economizer dry running

Can an exhaust gas economizer run dry, in case of emergency?
if yes, what precautions should be taken?


It is possible to operate the exhaust gas boiler in the dry condition in an emergency situation.
When doing so, additional care must be taken to prevent the outbreak of soot fires, as the risk increases due to the higher operating temperature on the tube surfaces.

Here is a list of general best practices to follow when running an exhaust gas economizer without water. However, it is important to refer to the specific section, in maker’s manual, on “dry running operation” for more detailed guidance.

  • The exhaust gas boiler must be water washed before the dry running operation (if possible).

  • The soot blowing frequency should be increased to 3-4 times per day.

  • The exhaust gas inlet and outlet temperatures have to be closely monitored.
    The temperature inside the boiler must not exceed 400ºC (the temperature limit may vary between makers).

  • Instrumentation such as the exhaust gas inlet and outlet temperature gauges and the U-tube manometer must be fully operational.

  • Continuous M/E low load operation should be avoided as much as possible.

  • The vent and drain valves must remain open.

  • In case the event of high draught loss (backpressure) the soot blowing frequency should be increased.

  • Internal inspection of the exhaust gas economizer at first opportunity and permanent repairs.