Definition: A system boiler heats your radiators directly and stores hot water in a cylinder, supplying multiple bathrooms at once at strong pressure. Typical installed cost: £2,200-£3,500.
vs combi
Choose a system boiler for two or more bathrooms or high simultaneous demand. The cylinder also pairs naturally with solar PV diverters and future heat pump conversion.
Efficiency
Modern condensing system boilers reach about 89% efficiency. Insulate the cylinder and pipework well to keep standing losses low.
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