Despite rapid changes, inadequate water pressure is still a problem for a large proportion of British homes with the installation of modern showering systems. Whilst we could write a book on water pressure and plumbing systems here is a brief summary of the types of systems around and what can be done to improve the pressure. A quick disclaimer at this point: before making any decisions or taking any actions based on this article please consult a qualified plumber.
Although there are others, most British homes have one of three general types of hot water systems:
1. The gravity fed hot water tank
This generally gives the lowest pressure of the three systems we are discussing as the pressure comes from the height from the point the water comes out in your bathroom (the tap or the shower head) to the base of the cold water tank in the loft or on the roof (called ‘head’). Generally with this system pressure can be boosted by a) raising the cold water tank, b) installing a pump, or c) installing a combi boiler or a pressurised cylinder (see below). Note: 1 bar of pressure = approximately 33 feet or 10 metres of head.
2. The combination boiler (combi boiler)
This is a medium pressure system as the modern combination boiler generally provides around 1.5 bar of water pressure. An older combi boiler will usually give lower pressure and is generally much less efficient in its use of gas. Although you cannot put a standard pump on this system there are specialist pumped water storage tanks that can provide increased combi boiler performance. You can of course change the system to a pressurised cylinder or put in a modern combi boiler if yours is an older model.
3. The pressurised cylinder
This system keeps the hot water tank under mains water pressure so if you have good mains water pressure this is a true high pressure system. There are many different pressurised systems that vary in their maximum pressure from 3 bar to 5 bar. This pressure comes from the mains so if the main is only 1.5 bar you will only get 1.5 bar out. You cannot put a standard pump on this system. However it is possible that the pressure can be improved with a specialist pump and tank set up that simulates a more powerful main.
Whatever decisions you make about your plumbing system always be aware of the amount of extra water that is used by increasing the pressure (and by association the flow rate) and always consult both a water system specialist and a qualified plumber. You need to do both because it is very difficult for plumbers to keep abreast of the latest advances in some of the areas we have covered as they are invariably so busy. It is therefore prudent to do the research, present your ideal solution to your plumber, and then ask them to make sure the chosen system is appropriate for your particular circumstances.