<P> A back boiler is a device which is fitted to a residential heating stove or open fireplace to enable it to provide both room heat and domestic hot water or central heating . The device is a water filled heat exchanger enclosed at the rear of the burning chamber with a hot water output at the top of the chamber and a cold water feed at the bottom . </P> <P> The back boiler is typically used with a gravity feed circuit to the hot water cylinder, with a vent or overflow to prevent excess pressure build up . It can also be connected to a series of radiators to provide central heating but requires an electrical pump to be fitted to circulate the hot water . </P>

How does a back boiler work on open fire
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