When installing solar thermal panels or heat pumps households will require a different cylinder to those traditionally used in the home to store hot water.
An ideal cylinder will act as more of a heat store, an the increased insulation will usually make them more bulky.
The required size will depend on the hot water demand but they usually start from 550mm width by 1200mm height.
A twin coil cylinder is necessary for use with solar energy as one coil will be receiving the heat from the collector on the roof and the other coil is used to supply heat from the other main heat source when solar energy is insufficient.
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