This was a replacement of a boiler that was installed about 20 years ago but the company went out of business. It kept having parts issues so we replaced the boiler with this Triangle Tube model. We also installed an indirect heater for domestic water. The coal boiler is still part of the system and the water does still flow thru it. Should some issue take place with the new boiler, the coal boiler with its conversion burner in it could in reality be brought back on line.