When should I get a

Gas Boiler Replacement 

The Sustainable Energy Association of Ireland (SEAI) recommends that you should replace or upgrade your gas boiler if it is more than 15 years old.


Even if there are no apparent problems, it’s unlikely to be running above 70% efficiency (new gas boilers are more than 90%) and reliability is likely to be an issue.

  •  Help it run more efficiently, reducing your heating costs

  • Reduce your heating costs by up to 25%

  • Improve reliability and safety

  • Improve your Building Energy Rating (BER)


How Much Can I Save by

Getting a Gas Boiler Replacement 

Save up to 20% operational improvement in efficiency. That means more than 25% in fuel savings.


Combine it with zoned controls and your savings can increase to over 35%

In other words, you can cut your fuel bills by a third by replacing an older, low efficiency gas boiler with a high efficiency gas boiler and zoned controls.


Ideally suited to homes that already have a traditional heating and hot water system which is linked to a separate hot water cylinder.

These boilers also need a cold water storage tank in the loft to feed the hot water cylinder as well as a tank that maintains the water level of the central heating system.


A regular boiler may be the best option for replacing an existing boiler if the property has an older radiator system, as it might not be able to cope with the higher water pressure that is delivered by system or combi boilers.

  • Perfect for homes where a lot of hot water is used at the same time

  • Ideal where there are two or more bathrooms

  • A good option in areas where water pressure is low

  • Compatible with solar water heating systems for a lower carbon footprint and lower energy costs


A combination or ‘combi’ boiler is both a high efficiency water heater and a central heating boiler in a single compact unit.

Combi boilers heat water directly from the mains when you turn on a tap, so you won’t need a hot water storage cylinder or a cold water storage tank in the roof space.

They are also very cost-effective and energy-efficient as water is heated instantly rather than being heated and then stored in a cylinder.


An added benefit is that hot water is delivered at mains pressure, which means that you could get a powerful shower without the need for a separate pump.

  • Compact sizes make combi boilers perfect for smaller properties

  • Ideal where there is little or no loft space

  • No need for a hot water cylinder allows increased living space

  • No cold water storage tank frees up a loft for conversion

  • No risk of loft pipework freezing

  • Less pipework in the home makes installation typically cheaper


Oil fired central heating boilers burn kerosene or heating oil. This is the most popular system where mains gas is not available.

An oil-fuelled central heating system works in the same way as a gas-powered central heating system.


There are now high efficiency combi and heat-only oil boilers available on the market. 


Oil combi boilers have internal hot water tanks to supply hot water. Whereas gas combi boilers have what’s called on-demand hot water.

  • Oil combi boilers are highly energy efficient, and you can save a lot of fuel by heating up water on demand.

  • The running costs of oil combi boilers is usually much, much lower than other types of oil and some LPG boilers.

  • Oil is a more efficient fuel than gas and LPG, so every unit of energy spent gives a much better return.

  • Newer oil boilers are condensing boilers, running at an efficiency of 90% and above, compared with 60% for older boilers.