The cost of replacing your gas or combi gas boiler, including installation, is around €2,000 to €3,000. The exact price will depend on the type of gas boiler you are installing and individual labour costs. It is recommended to replace your boiler after 15 years as its efficiency will begin to reduce, leading to higher energy costs. Servicing your gas boiler each year can help to extend its lifespan and maintain its efficiency.
How Much Is a Gas Boiler Replacement?
The cost of replacing your gas or combi gas boiler is around €2,000 to €3,000.
There are several factors that will influence the final cost, such as:
- The manufacturer
- The boiler model
- The capacity of the boiler
- Labour costs
The size of your home will dictate the size of boiler you need and thereby its cost.
Below, you'll find a comparison of the estimated price of a gas boiler based on its size:
| Size of Home | Boiler Size | Estimated Price |
|---|---|---|
| One to Two Bedrooms | 15–18 kW | €2,500 |
| Two to Three Bedrooms | 18–24 kW | €2,800 |
| Four to Five Bedrooms | 30 kW | €3,000 |
Source: Gasworks.ie
As we can see from the table above, for smaller homes and apartments, a 18kw gas boiler would be sufficient while for larger homes, it would be better to invest in a larger boiler bigger than 20kw.
Given the factors that influence the final cost, we recommend getting two or three separate quotes before making a final decision on the price you are going to pay. This way you can try and find the best price that suits your budget.
Combi vs. System Boiler Replacement?
When replacing your boiler, the first major decision is the type of unit.
This choice is primarily driven by your home's size and your household's hot water needs.
There are three common types, but you will almost certainly be choosing between a Combination (Combi) boiler and a System boiler.
| Feature | Combination (Combi) Boiler | System Boiler |
|---|---|---|
| Hot Water | Heats water instantly on demand. No storage cylinder required. | Heats water and stores it in a separate hot water cylinder (e.g., in a hot press). |
| Best For | Smaller homes, apartments, or 1-2 person households with a single bathroom. | Medium to large homes (3+ beds) or any home with 2 or more bathrooms. |
| Space Required | Very compact. Can often fit inside a standard kitchen cupboard. | Requires space for both the boiler unit and the hot water cylinder. |
| Water Pressure | Dependent on the mains water pressure. Pressure can drop if multiple taps/showers are used at once. | Delivers a strong, constant flow of hot water to multiple outlets simultaneously. |
| Installation | Generally faster and cheaper as it requires less pipework. | More complex, but often the necessary choice for larger Irish family homes. |
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What Is the Best Gas Boiler Replacement on the Market?
Given that the individual expectations, and budget, of someone purchasing a new gas boiler replacement will be different, it's difficult to give a definitive recommendation as to which is the best boiler available on the market.
What we can advise is the factors to take into consideration before buying a replacement boiler. By having an idea of this, you will be better placed to compare what is available on the market.
Factors to consider include:
- Budget — With prices starting from just above €2,000 and rising to €3,000+, your budget will largely dictate which boiler you choose.
- The length of warranty — Boilers can be expensive to service and replacement parts can take time to source, so by purchasing a boiler with a good warranty period you can offset these possible future costs.
- Boiler efficiency — It's important to buy a boiler with a high efficiency rating, otherwise you will be losing money on any energy wasted by the boiler.
- The size of your home — The size of your home will determine its heating needs. The bigger your home, the bigger a boiler you'll need. If you are living in a smaller property, a smaller, cheaper boiler might be sufficient.
Below you will find an overview table of some popular gas boiler brands and their estimated price range:
| Brand | Estimated Price Range (EUR) |
|---|---|
| Worcester Bosch | €2,500 - €3,500 |
| Vaillant | €2,500 - €3,500 |
| Viessmann | €3,000 - €4,000 |
| Ideal | €2,000 - €3,000 |
| Baxi | €2,000 - €3,000 |
When Should I Get a Gas Boiler Replacement?
Boilers normally require replacing after about 10 to 15 years.
Most gas boilers will continue to work perfectly for years, but will eventually start deteriorating after a while. There are some clear signs to watch out for when it comes to knowing when to replace your gas boiler:
- Boiler Age — Gas boilers will typically last between 10–15 years. If your gas boiler is approaching this age and starting to break down, it might be time to look into a gas boiler replacement.
- Inconsistent Heating and Hot Water — If you're getting inconsistent hot water from the tap, like if it's running cold and then hot again, it could be down to wear and tear and needing a replacement.
- Strange Noises — If your boiler is constantly making banging or clanging noises, you should have it checked out immediately. Your plumber will be able to determine if you need a gas boiler replacement.
- Major Leaks — If you're having constant leaks and water is dripping from the boiler, it might need to be replaced if the parts can't be found for it.
- Yellow Flame Instead of Blue — A yellow or orange flame instead of a crisp blue flame can indicate incomplete combustion. This is a serious problem that can produce carbon monoxide, so you should get it replaced as soon as possible.
- Increased Energy Bills — Since gas boilers become less efficient with age, it might lead to your energy bills increasing. This can happen when your gas boilers need to try harder to reach the same performance and so add to your home heating bills.
Is It Better to Service or Replace My Gas Boiler?
Given the cost of a new boiler, you might want to consider servicing your boiler, especially if it isn't that old or only a couple of issues that could be fixed by bleeding your boiler. Servicing a gas boiler will cost roughly €130.
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How Do I Get a Gas Boiler Replacement?
If you're certain that your gas boiler is broken and needs replacement, you should definitely look into getting it done as soon as possible.
Getting a replacement can take a bit of time, however, so you should follow these steps to get it done in a straightforward way:
- Details About Your Current Boiler — Make sure you know what type of boiler you have and how long you've had it. This will help a gas boiler company or engineer understand your needs.
- Quotes — Shop around for different boiler quotes and find out how much it will cost to replace. In some instances, if you have boiler insurance or cover, you might be able to get a discount on the cost of a new boiler.
- Assessment — You'll need to get an assessment from a gas registered engineer to get an idea of what you need and what your property may require when it comes to your heating. The engineer will usually be from the same company as your boiler cover.
- Installation — Once you've decided on the quote, you will need to get it installed. This must be done by a Registered Gas Installer (RGI) as you cannot install your own boiler. After installations, your engineer will double-check to see if everything's in good working order.
How Efficient Is My Gas Boiler?
To know how efficient your gas boiler compare to others such as electric, condensing or biomass boilers, you first need to look at its energy efficiency rating.
You can find these labels on various energy appliances in your home. Here is what these labels mean:
- A rating — Your gas boiler works at 90% efficiency or more.
- B rating — Your gas boiler functions between 86-90% efficiency.
- C rating — Your gas boiler runs between 82-86% efficiency.
- D rating — Your gas boiler performs at 78-82% efficiency.
- E rating — Your gas boiler operates at 74-78% efficiency.
- F rating — Your gas boiler runs between 70-74% efficiency.
An inefficient gas boiler will use more units of gas than necessary to heat your home and water.
Using Ireland's average gas usage for a three-bedroom house, the yearly gas cost is approximately €1,403 including VAT.
An inefficient gas boiler, therefore, costs you the following:
| Gas Boiler Efficiency Rating | Extra Gas Cost Per Year | Estimated Time to Pay Off a New Boiler |
|---|---|---|
| B rating - 86-90% | €55 | N/A |
| C rating - 82-86% | €112 | 30 years |
| D rating - 78-82% | €168 | 20 years |
| E rating - 74-78% | €225 | 15 years |
| F rating - 70-74% | €280 | 12 years |
| G rating - under 70% | €420 | 8 years |
How Long Does a Gas Boiler Replacement Take?
A gas boiler replacement usually takes between 2 and 3 hours. Depending on the complexity of your gas boiler installation, it may take multiple hours to get your gas boiler installed.
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Are There Gas Boiler Replacement Grants?
No, there are no direct gas boiler grants or SEAI grants for any type of boiler available in Ireland.
The government is aiming to phase gas and oil boilers out of the market by 2025 due to our Paris Agreement commitments.
However, there are some other options you can take advantage of when trying to boost the heating efficiency of your home.
On top of this, there are alternative heating grants available from the SEAI for:
- Heat pump systems.
- Solar water heating systems.