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Which hot water cylinder is right for you?

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Let’s face it, water cylinders aren’t glamorous but whether you’re looking to save space, money, heat water quickly or after good heat retention it pays to look a little deeper and find the cylinder that will offer your customer exactly what they need.

Ok, so what’s new?

As new energy technologies become more popular, modern cylinders have been developed to better suit the requirements of a range of uses.

The industry standard has been the same for years – a cylinder with a separate wall-mounted expansion vessel, but this is being superseded, where practicable, by a range of more efficient unvented units.

The new ‘bubble top’ or ‘air gap’ systems no longer need a separate expansion vessel as a bubble of air is held at the top of the cylinder and the water is drawn from the side or a top-mounted pipe that reaches down inside the cylinder.

Usually there’s a floating plastic baffle that sits on top of the water to separate it from the air bubble. This baffle moves up and down as the water heats and cools.

When the system undergoes its annual service, the engineer should check the air gap and regenerate as necessary of there will be pressure problems, but it’s a simple solution.

Better efficiency?

ERP has had a significant effect on the design of cylinders too. These days, products with an ERP of C or below are basically a no-go, and manufacturers have stepped up to the mark with products providing better performance and energy efficiency.

There’s also vacuum panel insulation, which works more efficiently than Polyurethane foam, which coats most cylinders used.

Hard or soft?

In hard water areas it’s worth looking at models that don’t rely on heat exchangers and these can harbour and encourage limescale deposits.

Manufacturers have developed heat exchange coil designs, along with tank in tank technology, to optimise economic heat recovery, and reduce scale build up.

Making space

Many homeowners would rather have a smaller unit that allows them a bit of extra storage in their airing cupboard.

Most cylinders come in capacities between 100 and 300 litres and designers are canny. They have caught onto the fact that a few millimeters added to the cylinder’s diameter can significantly reduce its height.

Another option, which minimizes external pipework and optimises usable space around the cylinder are designs where the heating coil, hot and cold water services, expansion vessels and safety valves are concealed in a contained section with a removable lid.

There are also slimline and horizontal designs available to solve particular installation challenges. These are more pricey, but they may help you out of a tight spot.

A bit of research and a fresh look at a familiar piece of kit is well worth the trouble. To see the full range of our plumbing and energy efficiency courses, please click here

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