How Hard Is the Water in Surrey and Sussex?
The RH and BN postcode areas sit on and around the North and South Downs chalk formations, which produce some of the hardest water in England. Water hardness is measured in mg/l (milligrams per litre of calcium carbonate). Areas with readings above 200 mg/l are classified as "very hard".
Parts of Reigate, Redhill, Merstham, and Caterham regularly record readings above 300 mg/l – among the highest in the UK. Even coastal areas like Brighton and Worthing, while somewhat softer, still have hard water relative to much of the country.
What Hard Water Does to Your Boiler
When hard water is heated, calcium carbonate precipitates out and forms limescale. Inside a boiler, this builds up in the heat exchanger – the component that transfers heat from the gas flame to the water in your pipes. The consequences are:
- Reduced efficiency – limescale acts as an insulator, forcing the boiler to work harder and use more gas
- Overheating – restricted flow through a scaled heat exchanger causes localised overheating, leading to noise (kettling) and premature wear
- Component failure – limescale build-up is one of the leading causes of heat exchanger failure, which is one of the most expensive boiler repairs
- Blocked condensate traps – limescale can block condensate traps on condensing boilers
How to Protect Your Boiler
- Scale inhibitor – a chemical inhibitor added to the central heating system water reduces limescale formation significantly. We add inhibitor as standard during all installations and annual services.
- Magnetic filter – a magnetic filter (such as Magnaclean) is fitted to the pipework near the boiler to capture magnetite (black sludge) before it enters the boiler. Essential in hard water areas.
- Scale reducer/limescale protector – fitted on the mains cold water feed to the boiler, these physically or chemically treat the water to reduce scale formation.
- Annual servicing – regular servicing allows us to monitor scale levels and take action before serious damage occurs.
What to Do If Your Boiler Is Already Scaled
If your boiler is noisy (kettling) or inefficient, it may already have significant limescale. A chemical de-scale treatment or a power flush can remove existing scale and sludge. Contact us and we'll assess the best course of action for your specific boiler and system.