Cylinders


A Hot Water Cylinder in a traditional heating system holds a large quantity of hot water that is available immediately (or as soon as the feed allows). Most of the cylinders we install are indirect, which means water from the central heating goes through a coil within the cylinder giving its heat up to the water within the cylinder.





Most modern cylinders come with foam lagging bonded on to the outside of the cylinder. This acts as an efficient insulator and will keep the water hot for a considerable time. Where you install the cylinder dictates the shape and size you require, but the capacity of the cylinder is important.


There are lots of different types of cylinder available, all of which basically store and supply hot water, but in different ways. There are 5 main types of cylinder. See below

Direct - which are use with Circulators because the water is heated directly.

Indirect – This type is used for any type of central heating system. The water from the central heating goes through a coil of pipe in the cylinder (which heats up to the water in the cylinder) it does not mix with the water in the cylinder. This type of cylinder will have an air bleed on a pipe at the side, we suggest the pump and motorised valves are located in the same cupboard if possible.

Primatic (self priming) – Is used with gravity systems due to the water for the central heating is taken from in the cylinder, and is separated by an air lock.

Thermal Storage - The cylinder is large and the main cold water is passed through a coil in the cylinder taking its heat from the thermal storage and supplying the hot taps. The central heating circuit is also taken from the cylinder.

Unvented Cylinder - This is the same as an indirect cylinder but there is not a header tank, it is connected directly to the main water supply giving mains water pressure to the hot taps and showers. This is ideal for the larger home.

3 reasons to use Always Plumbing


Local Company Serving Local People

Always Plumbing is a local company based in London Colney, St Albans in Hertfordshire with over 30 years experience in the trade, from small jobs to the more complex domestic jobs.

Based in St Albans

The company is based in London Colney St Albans and covers all of Herts, Beds and Bucks as well as London. We have a highly trained team of plumbers and central heating engineers that will make sure your plumbing, boiler or service required is maintained to the highest standard.

All Safe (formerly CORGI) gas engineers

Always Plumbing is your one-call service for all your plumbing and heating needs in your local area, With highly trained plumbers and All Safe (formerly CORGI) gas engineers we will respond quickly to any emergency.

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