boiler operations are fine tuned to minimize thermodynamic losses and pressure losses across throttle valves at the output of a boiler . whenever the boiler is operating outside of desired operating levels , the first action considered is to reduce spray flows into steam supplied into a reheater or superheater outputting steam at too low of a temperature . the second consideration is to reduce the use of auxiliary electrical power , such as fans supplying tempering air to the primary air used to carry fuel to the burners . the next consideration is selective soot blowing and damper adjustments to redistribute heat in combustion product exhaust gas in the boiler . then , if possible , the quantity of flue as recycled is adjusted to modify the gas temperature and the heat transferred in the radiant sections and the convective sections of the boiler . finally , when possible the burners are tilted or biased to move a combustion region of the fuel up or down in the furnace section of the boiler . burner vanes are set affecting fuel - air mixing and pulverizers are adjusted modifying fuel particle size to alter both the size and position of the combustion region in the boiler . an expert system may be used to provide diagnostics and advisories to a human operator of the boiler who can then more efficiently operate the boiler .