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Gas System Boilers

A gas system boiler is very similar to the conventional regular boiler set up, but with most components that make up the standard gas central heating system incorporated into the boiler system directly.

The simple set up of gas system boilers allows for a quicker installation and results in a more cost-effective central heating system.

At Direct Heating Supplies we sell a vast range of system boilers from leading brands including Worcester, Vaillant, Baxi and Ideal.

Please note all boiler purchases must be made online and cannot be made via the customer service phone line.

Boilers do not come with a flue, flues can be purchased separately here or you can purchase a boiler pack which includes your boiler and flue or boiler, flue and timer.

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What is a System Boiler?

Gas system boilers require a hot water cylinder for storing hot water, yet, the major heating components are integrated into the boiler itself making it easier to install. Unlike heat only boilers, there is no need to install a water tank in the loft, this makes gas system boilers ideal for properties where loft space is limited.

  • Ideal for homes with more than one bathroom
  • Continuous source of hot water to multiple taps at once
  • No need for installing a water tank, eliminating worries about leaks or frost damage
  • Extremely cost-effective
  • Built-in components, compact within the boiler, making installation quick and simple

Advantages of System Boilers

Hassle-free installation

Installing a gas system boiler can be a quicker and hassle-free process, compared to other heating systems. The main components for heating and hot water are compressed within the boiler itself. By building in components, the unit is more compact, and the only additional requirement is a hot water cylinder , which is then stored within an airing cupboard. Making installation quicker and neater.

Stronger water pressure

Unlike heat only boilers which rely on gravity to send water down the pipes, gas system boilers have water supply delivered via the mains, eliminating the use of a tank in the loft. Nevertheless, this means the water supplied will be at higher pressure.

Ideal for properties which have a high hot water demand

As a system boiler uses a large cylinder, you have instant access to large amounts of hot water. This means you can use multiple taps simultaneously without loosing water pressure. This feature makes the system boiler ideal for larger houses with a higher hot water demand.

Fast and cost-effective

System boilers include a pump, which means it responds quickly and has more economic running costs.

No need for a cold-water tank

System boilers don’t require a feed and expansion tank, or a cold-water feed tank as they can be used with pressurised cylinders. This can save space and still gives you the option of having a system boiler even if you don’t have a loft.

What is the best System Boiler?

Direct Heating Supplies sell an extensive range of system boilers from the UK’s largest manufacturers, like Worcester Bosch, Vaillant, Ideal, Baxi, Glow-Worm, Potterton and Viessmann. Each manufacturer has a system boiler to suit homes of different hot water and heating demands and come with different warranty periods, so there is a system boiler which will suit your needs.

Factors to Consider with System Boilers

System Boilers may require more space

Although there is no need for a cold-water feed tank, system boilers can require more space than a combination boiler, as the system requires a hot water cylinder. A system boiler will not take up as much space as a heat only (regular) boiler.

Your hot water cylinder needs to be well insulated

To ensure no heat is wasted, your hot water cylinder needs to be properly insulated to keep heat in and reduce energy waste. Although, this is seen as more a consideration rather a disadvantage as insulation for your hot water tank is straightforward and extremely cheap.

Your hot water may not be instant

The size of your hot water cylinder will determine how much hot water you can store and use before having to fill the tank up again.

System Boilers Explained

Watch Worcester's video "System Boilers Explained" to find out more about regular boilers and when they should be installed.