There are various types of water cyclinders (or water heaters) on the market but generally they all use the same principle to heat the water.
The water for most systems is commonly fed from a cold water tank (called a cistern) in the loft. In a direct cylinder system the water is preheated by the boiler and pumped in to the water cylinder for storage.
In an indirect cylinder system the water in the cylinder is heated by a coil at the bottom. This coil is heated by hot water by the boiler.
Smaller water boiling systems use an electric immersion heater.
The water for most systems is commonly fed from a cold water tank (called a cistern) in the loft. In a direct cylinder system the water is preheated by the boiler and pumped in to the water cylinder for storage.
In an indirect cylinder system the water in the cylinder is heated by a coil at the bottom. This coil is heated by hot water by the boiler.
Smaller water boiling systems use an electric immersion heater.
