Everything You Need To Know About Boiler Cylinders

Everything You Need To Know About Boiler Cylinders

Posted on November 23, 2016

As winter arrives and the weather turns colder, many people start to worry about their heating system failing and perhaps wonder if they should be considering a boiler replacement.

If your existing system has a hot water cylinder, you may think that changing the boiler means you’d have to switch to a combi system that does away with stored hot water, but that’s not the case. You have to have a condensing boiler when you upgrade your system, but that needn’t mean losing your cylinder.

The Cylinder Advantage

The main benefit of a hot water cylinder is its ability to supply several outlets at the same time with minimal loss of pressure. So if you have a big family or multiple bathrooms, it makes sense to have a cylinder system.

Boilers that support cylinders generally need less complex circuitry than combi types, so if you need boiler repairs, they will likely be cheaper and easier.

You’ll also need a cylinder if you want to take advantage of solar hot water heating. This allows you to take advantage of storing water heated during the day. If you’re replacing a cylinder with a view to getting solar water heating in future, it’s worth getting a twin-coil type where one coil is linked to the boiler and one to the solar panels.

Assessing Your Needs

If you’re considering a boiler replacement, it’s important to look at your home’s requirements for hot water. Smaller properties and those with a single bathroom may well be adequately served by a combi boiler with no need for a hot water storage cylinder.

If you have a larger house and extra bathrooms or en-suites, then keeping a cylinder makes more sense. Cylinders come in different sizes, so if you regularly run out of hot water, it may be worth getting a bigger one. Modern cylinders have efficient insulation built in, so they can keep stored water hot for a long time – the manufacturers should give heat-loss figures to allow you to compare different models.

Cylinder Types

We’ve already discussed single- and dual-coil types of cylinder for use with solar panels, and different sizes of cylinder. It’s also important to note there there are also vented and unvented types.

A vented cylinder draws its water supply from a separate cold water tank in the loft and is heated by what is known as a ‘regular’ boiler. With unvented cylinders the system is sealed and water is delivered from the mains. Changing from a vented to an unvented system will do away with the need for extra water tanks.

Most cylinders also have provision for an electric immersion heater, allowing you to heat water without having to run your boiler.