How Long Do Hot Water Cylinders Last?

Hot water cylinders are a crucial component of our daily lives. They provide us with heated water for various purposes but, unfortunately, they do not last forever. On average, a properly maintained hot water cylinder can be expected to last anywhere between 10 and 20 years, depending on the contents and pH neutrality of the water it’s storing. In near-optimal conditions, we occasionally hear of cylinders lasting for 40-50 years, but this is rare.

The factors which can influence a cylinder’s lifespan, include:

Material Grade

As you’d expect, cylinders manufactured from thicker grades of metal take longer to corrode. The thinner and arguably lower-quality alternatives do of course cost less to buy, but don’t be surprised if they don’t last very long. An expensive cylinder doesn’t necessarily mean thick materials, so always check and compare the specifications.

Regular Maintenance

Having your hot water cylinder regularly serviced and maintained can have a significant effect on its lifespan, especially when it comes to unvented cylinders. This is because cylinders are designed to work within specific pressure and temperature ranges, and if the components which regulate these factors ever fail to do so, the cylinder can be subjected to excessive amounts of stress and strain.

Water “Quality”

While quantifiable data on this subject is in short supply, we believe that the corrosion of copper and stainless steel occurs most quickly in areas where the water is more towards the acidic end of the pH scale. We also believe that this is more common in private water sources (like wells or boreholes) where little to no neutralisation of acidity takes place.

Limescale and Water Softening

It is our understanding that a thin layer of limescale can be beneficial to a cylinder’s lifespan, as it provides protection against acidity and other corrosive factors. Using completely softened water means that the cylinder loses (or never has the chance to build up) this protective layer and so can corrode more quickly. Too much limescale can also be negative though, as it can inhibit the heat transfer from the coil and lead to reduced efficiency.

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In conclusion, the lifespan of a hot water cylinder can vary depending on several factors, such as the grade of the cylinder’s manufacturing materials, the pH level of the water in the area, the regularity of servicing, and how much the water has been softened.

If you want to protect yourself against a cylinder, which will inevitably leak one day, we can manufacture Drain Trays. This is a tray in which your cylinder can sit and has a drain connection that can be piped to a suitable termination point, similar to an overflow pipe from a header tank.

Photo Credit: Image by stefamerpik on Freepik