Five steps to unvented cylinder success

Choosing an unvented hot water cylinder can be a minefield for installers, with an increasing number of manufacturers having brought products to market to capitalise on the demand for high pressure, high performance hot water. It’s important to choose a well-made, high-quality, efficient cylinder, else the result might be costly, time-consuming call backs and unsatisfied customers.
With this in mind, Heatrae Sadia has put together some top tips to help with product selection.
Megaflo Eco cylinder1. Material matters
As unvented cylinders store water under pressure, it’s essential that they’re strong, durable and corrosion resistant. In the UK cylinders are generally made from stainless steel, copper or glass lined mild steel, but Duplex stainless steel is the preferred material, as it has outstanding and unique corrosion resistant properties. It’s also lightweight, giving it a strength-to-weight ratio advantage.
It’s worth considering that cylinders made from mild steel will require a coating or glass lining to make them corrosion resistant. They also need a sacrificial anode, as do some cylinders made from lower-grade stainless steel, which will need to be monitored for signs of erosion each year.
2. Energy efficiency and innovation
Leading manufacturers invest in research and development to ensure their products meet the needs of installers and end users by making them more energy efficient, forward-thinking and flexible. These added benefits are unlikely to be offered by the manufacturers of low-cost unvented products. Heatrae Sadia’s Megaflo Eco, for example, offers reduced heat loss for added efficiency, and a solar thermal version is available. Furthermore, pre-plumbed and pre-wired versions make installation even easier.
3. On par performance?
Market leading brands will also invest in the performance of their products, whether that’s by improving flow rates, recovery times, the amount of stored hot water available or standing heat losses. Before specifying a hot water cylinder, it’s worth checking its vital statistics against other products, as an underperforming product will lead to an unhappy customer.
4. Peace of mind guaranteed
Customers will expect their new hot water cylinder to have a long and reliable life, so ensuring the product has an extended or comprehensive guarantee will offer peace of mind that should anything go wrong, they will be covered. Installers should check the terms of any guarantee offered, and make homeowners aware of any limitations hidden in the T&Cs. Particular things to check are whether onsite parts and labour costs are included, whether the guarantee is transferrable to new owners if the property is sold, and what the level of support offered is like.
5. Up to standard
By checking a cylinder’s credentials, installers will have extra reassurance that the product has been properly manufactured, is built to last and will operate safely.  Installers should look out for hot water cylinders that are constructed and tested to established British and European standards, as well as being manufactured in a factory which has accredited Quality Management Systems. Third party approvals – such as from WRAS and KIWA – demonstrate good quality and performance.
On face value, all unvented cylinders might look the same, but closer inspection will reveal important differences. High-quality products offer the best possible performance, efficiency and innovation and good value for money – and will ensure customer satisfaction in the long run.
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