Click here for numbers of run hours for boilers 3 & 4.
Click here for a summary of UVMMC’s boiler comparison study & a 1-paragraph intro to the paper “Thermoacoustic Vibrations in Industrial Furnaces and Boilers”
Click here for a brief description of ‘nulls’ for the stack silencer (frequencies where it does not reduce the noise much) and two graphs.
Click here for a brief primer on resonance in tubes (such as the boiler) and “rumble” (i.e., low frequency noise) in boilers.