Our electric water heaters have been installed in many different applications, but do you know just how important the materials used in their construction are in terms of ensuring longevity?
Small unvented and vented electric water heaters are extremely popular, with demand for them growing year upon year. While energy efficiency remains a key factor, we’re also aware our hot water units must remain resistant to corrosion if they’re to stand the test of time.
Corrosion can be caused by many things, including hard water, which is particularly common throughout eastern parts of the UK. Dissolved minerals present in hard water can build up inside tanks and turn into limescale – preventing heat from escaping naturally, causing high pressure and overheating. Limescale deposits can also work their way inside valves and connections, resulting in blockages, pressure problems and leakages.
To combat this, many electric water heaters use sacrificial anodes to attract any minerals away from the surface of the unit itself and prevent corrosion. We’ve found these anodes to be effective in hard water areas, as the higher level of mineral ions in the water ensure greater levels of conductivity.
Sacrificial anodes need to be replaced regularly (usually every one or two years), so it is important to check your water heater offers good access to them for easy maintenance. That’s why compact units such as our Andris Lux utilise a robust four-bolt flange to ensure replacement of the sacrificial anode is simple and straightforward. You should definitely bear this in mind when specifying or installing an electric water heater!
By contrast, soft water has lower levels of electrical conductivity, so does not react in the same way. For systems in soft water areas, a powered anode is used (with an electrical supply running through it to inject a low current into the water) to create the same protective effect. These types of anode are made from titanium, rather than magnesium.
Titanium provides greater longevity compared to nickel alloy and copper alternatives. Boasting high levels of protection against scale and corrosion, it’s no surprise to see it lining the insides of the latest electric water heaters. Titanium (and titanium alloys) offer exceptional chemical resistance, due to a dense, self-sealing oxide layer – perfect for preventing limescale from building up inside a hot water unit.
Modern electric water heaters such as our Pro1 Eco and Velis Evo range benefit from titanium lined tanks and magnesium anodes, ensuring exceptional durability and an extended lifecycle. Titanium enamelling is also acid and alkali resistant – as well as exceptionally strong – so is ideal for water storage products in soft or hard water environments.
With the market for electric water heaters remaining buoyant, it’s important to select models that are well constructed, made from quality materials and built to last. As water quality varies throughout the UK, electric water heaters should be chosen safe in the knowledge they remain resistant to corrosion, ensuring a long-lasting and energy-efficient lifespan.