Fuel savings

[carlstadt]

We have two Cleaver Brooks fire tube boilers. We have a CB400-600 and a CB 657-350. The 600hp can run on gas or oil, the 350hp can only run on oil. Do to productin requierments we use only one boiler, we prefer to run on gas so we use the 600hp. We are thinking of converting the 350hp to gas. My question is, does a small boiler use less gas than a larger one to make the same amount of steam? Thank You; Bill

 

[skbutler]

carlstadt, yes and no. A 600 hp CB will have a different radiation loss than a 350 hp CB boiler but this should be of little concern. The big factor is your load. A firetube boilers operate at higher efficiencies at higher firing rates (generally.) So, if you have a 275 hp load, the 350 hp CB, operating at a higher firing rate, will meet the load more efficiently than the 600hp CB operating at the lower end of its firing rate.