There are a couple of types of hot water cylinder and they are listed below.

In-direct.

This type of indirect cylinder is internally fitted with something called a heat exchanger, which is actually a coil through which the water will pass. It is normally heated from a boiler or even solar powered technology. The Cold Water feed goes on the bottom of the cylinder, where there is usually a small drain cock. The hot water is then returned to the hot water cylinder through a connection at the top of the cylinder. The actual heat transfer takes place from the heated coil of water to the water that is sat inside the cylinder. The two never meet. Therefore the name ‘indirect’ refers to the relationship between the coil and the stored water, in other words the heat is indirectly transferred to the water. A Holland Park Plumber is well trained in this type of system. This type is available both as a vented or unvented cylinder. Hot water leaves the tank at the top.

The Direct.

The direct cylinder is different in that an electrical element does the heating of the water rather than an outside source, so which can only happen via an electrical supply. This is a good option for small flats and apartments. When the heating is done, the hot water is fed perhaps to a bath. There are very large cylinders of the direct kind available which have two/three elements to give a huge supply of hot water as required. Again they are available in vented or unvented examples. Holland Park Plumbers understand these systems. This type has the advantage of exploiting the various additives in the fed boiler water and so prolongs its life quite considerably.



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