When To Replace Your Boiler

As a homeowner, you may find yourself wondering whether to repair or replace your boiler. There are several factors to consider when making this decision, including the age and condition of your boiler, the cost of repairs, and the efficiency of a new boiler.

When so much money is spent on heating and hot water bills, there comes a time when your boiler, no matter how good you think it is, is performing so badly it needs to be replaced.  You may not be aware of its efficiency until an engineer checks it and tells you. 

Here, we look at the main signs to look out for when it’s time for a replacement boiler.

Warning signs a boiler needs replacing

There are several clear warning signs that indicate your boiler needs to be replaced:

  • Frequent breakdowns and the need for repairs
  • Difficulty finding replacement parts due to your boiler’s age
  • A noticeable decline in your boiler’s efficiency and performance
  • Strange noises like banging or humming coming from your boiler
  • The boiler gives off a bad smell, even after a service.
  • Leaks around your boiler and water dripping from pipes
  • An increase in your monthly energy bills despite no change in usage

If you notice any combination of these signs, it’s time to start planning for a boiler replacement. Don’t ignore the signs, as continuing to repair an aging boiler may end up costing you more in the long run.

When to replace your boiler

The average lifespan of a boiler

The average lifespan of a boiler is between 10-15 years. This can vary based on the original quality of the boiler, whether it has been properly maintained and serviced, and the quality of any repairs done.

Boiler TypeLifespan
Standard10-12 years
Combi12-15 years
Condensing15-20 years

With regular maintenance, a high-quality boiler may last 15 years or longer before needing replacement. But once a boiler is 10+ years old, it’s a good idea to start budgeting and planning for a new one, even if your current boiler seems fine. As the boiler ages, issues like declining efficiency often start emerging.

Should I repair or replace my boiler?

If your boiler is more than 15 years old, it is likely that repairs will be more expensive than the cost of a new boiler. A new boiler will also be more energy-efficient, which can save you money on your energy bills.

If your boiler is less than 15 years old and is in good condition, it is likely that repairs will be less expensive than the cost of a new boiler.

However, you should still consider the efficiency of a new boiler when making your decision. The best way to determine whether to repair or replace your boiler is to consult with a qualified heating contractor. They will be able to inspect your boiler and provide you with a professional opinion.

How often should a boiler be replaced?

This depends on each individual boiler in terms of the quality of its initial installation, the condition of the heating system such as radiators; whether it has been well maintained with annual servicing and if genuine manufacturers’ parts have been used during repairs. 

If well maintained, it can last around 15 years before other factors make a replacement boiler necessary.

How much does it cost to replace a boiler in 2023?

The cost to purchase a new boiler can range from £500 – £3,500 depending on the type, brand, features, and output size you need. Installation costs typically range from £1,500 – £3,500 depending on your location and the complexity of the job.

New boiler and installation cost estimates

  • Basic combi boiler replacement: £2,000 – £2,500 total
  • New combi boiler, new location: £3,000 – £4,000 total
  • Replace standard with combi: £3,500 – £4,500 total
  • Full heating system upgrade: £5,000+

Get multiple quotes to compare pricing for both the boiler unit and installation.

Boiler installation timelines

Boiler installation timelinesTime requiredFastestFactors affecting installation time
Basic combi swap1-2 daysYesBoiler type and location – Combi swaps are fastest
Combi with new piping2-3 daysNoScope of additional work needed – Upgrades add time, Home layout complexity – More piping equals more time
Moving boiler location3+ daysNoScope of additional work needed – Upgrades add time, Home layout complexity – More piping equals more time

Some of the most popular brands of boiler are found in this article: 5 best-selling combi boilers from famous brands like Worcester Bosch, Baxi and Vaillant. 

Weighing repair vs replacement costs

To decide whether to repair or replace your aging boiler, compare the repair costs over the past year to estimates for a new boiler:

  • Add up all service call fees, parts, and labor for repairs
  • Factor in projected future repair costs based on current issues
  • Compare that total to quotes from installers for a complete replacement

Repairs that exceed 20% of a replacement’s cost in a 1 year period typically indicate replacement is the more cost-effective option.

Additionally, a new energy-efficient boiler can yield long-term energy savings that offset some of the upfront replacement cost over 5-10 years of use.

Heating engineers recommend proactively replacing your boiler once it reaches 10-15 years old. Parts become difficult to source past this age, and efficiency declines annually.

Annual servicing can prolong a boiler’s lifespan. But once issues emerge, replacement is better than continuing repairs.

Experts suggest getting quotes for both repair and replacement if your boiler is over 10 years old. This allows for an informed decision based on costs.

Grants and rebates for new boilers

There are a few government schemes that provide grants and rebates to help homeowners cover the cost of upgrading an old, inefficient boiler:

  • The Boiler Upgrade Scheme provides £5,000 grants in England and Wales
  • Home Energy Scotland offers interest-free loans up to £17,500

You may also qualify for rebates through:

  • The Energy Company Obligation scheme
  • Your local council
  • Energy suppliers

Check eligibility criteria before applying. Rebates can save you several hundred pounds off the total replacement cost.

signs you need to replace your boiler

Are gas boilers being phased out?

Fossil fuel heating appliances like will eventually be phased out from newly-built homes but there are no plans to ban gas boilers from existing homes. So you can still buy a brand new gas boiler that will serve you well for many years. 

At the moment government policy seems to be gas heating will be banned in only new build homes by 2025 but this could easily be postponed.