Cylinders

"A hot water storage cylinder is a tank that stores your hot water. This is specificly for the hotwater that comes out of your taps. The benifit of having a cylinder is that you will not loose pressure when hot water taps are being used at the same time. There are 2 different types of cylinder 1) VENTED - Means that the water going into the cylinder is fed by a cold water tank above it. This is also called a gravity system as it requires gravity to feed the tank and get hot water. 2) UN-VENTED - The modern style that does away with the tank above and fills the cylinder straight from the mains. Most of these have the option to have an immersion heater as a back up. This setup is called a sealed system Both of these types of boilers have the following options of how the water is heated once its in the cylinder. 1) DIRECT - This means that the water in the cylinder is heated by an element inside the tank called an immersion heater these are only powered by electric. 2) IN-DIRECT - This means that the water in the hot water cylinder is heated by an external source like a boiler. This leaves your with 4 options If you need a cylinder that is fed from the mains water and you want to heat the hotwater by a boiler, you need an Unvented INDIRECT Cylinder. If you need a cylinder that is fed by the mains but you want to heat the hot water with electricity you need a Unvented DIRECT Cylinder. If you need a cylinder that is fed by a tank above the cylinder and powered by a boiler you need a VENTED indirect Cylinder. If you need a cylinder that is fed by a tank above the cylinder but powered only by electricity you need an UNVENTED Direct Cylinder."