Cordivari BOLLY 1 ST FB WB hot water boiler with 300 litre fixed heat exchangerCordivari BOLLY 1 ST FB WB hot water boiler with 300 litre fixed heat exchanger The Cordivari BOLLY 1 ST FB WB 300 liter hot water boiler is a thermal accumulator designed for the production and storage of domestic hot water for integration with traditional, solar, or biomass systems. The domestic hot water boiler is a storage tank capable of holding large quantities of water, maintaining it at the desired temperature. Producing domestic hot water for