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Repair your boiler, or replace your boiler? Find out what's best for you

Nobody wants to buy a new boiler, ever. But, if your boiler is losing pressure on a regular basis, or making more noise than Trumps twitter account, a replacement may just be the only option.

The majority of boilers (if serviced regularly) can last between 10 to 15 years, sometimes more (if you're lucky).

But, there are no hard and fast rules, sometimes a boiler may need to be replaced sooner, so how do you know when it’s time to buy a new boiler? 

In this post we will run through some of the common boiler bugs, and whether it makes sense to repair it, or replace it

Let's dive in...

#1 — Simply put, it’s just not working like it used to

Repair or Replace Boiler If Not Working Properly

Even though you may have had your boiler serviced annually, it may eventually stop performing its function (heat and hot water).

If you are finding that your radiators aren't getting as hot as they used to, or the hot water is fluctuating, it could be a sign of something serious.

Sometimes, these issues can be caused by a leak or blockage in the system somewhere, so seek the assistance of an engineer fast.

Likely cause(s) Likely fix Cost to repair
System Blockage Powerflush of system £200-500
Faulty Heat Exchanger Replacement Heat Exchanger £200-£600
Faulty Diverter Valve Replacement Diverter Valve £200-500


If your boiler is less than 8 years old, we'd reccomend having it looked at by a local Gas Safe engineer.

If your boiler is 10+ years old, you may want to seriously consider a replacement.

To see how much a new boiler could cost, click here to get a free quote (and the best deal)


Good reads for you:

#2 — It's regularly breaking down 

Boiler Breaking Down Repair or Replace

Are you having to call an engineer out to get your boiler up and running far too often?

If your boiler is requiring multiple call outs within a year, it’s worth considering how much this may cost you going forward and whether a new boiler may be less costly. 

Annual servicing should keep your boiler running well for the rest of the year, so if your boiler is malfunctioning after a service, it’s an indication that it may be time for a replacement. 

Likely cause(s) Likely fix Cost to repair
Component failure(s) Replacement of key components £300-600 (per component)


If your boiler is less than 8 years old, repairing it would still make sense (pending it's nothing too serious).

First, get an engineer in to see which component has failed, and go from there.

However, again, if your boiler is 10+ years old - regular breakdowns are worrying. It's trying to tell you something.

Heatable supply and fit new boilers from just £1,595 - get a free quote online.

Good reads for you:

#3 — It's leaking (losing pressure) regularly

Boiler Leaking Losing Pressure

If your boiler is leaking water, then it’s a sure sign that there is a fault somewhere (which could be costly).

Typically, this is due to a broken seal or valve inside the boiler; however, sometimes it can be due to major corrosion of an internal component (such as a heat exchanger).

It’s important to get a leak fixed as soon as possible, since the water can cause further damage to internal components or potentially cause structural damage to your property. 

Likely cause(s) Likely fix Cost to repair
Pipework leak (joint or seal) Finding and repairing leak £100-300 
Leak from heat exchanger Replacing component £200-600
PRV failure (pressure release valve) Replacing component £80-250


If your boiler is less than 8 years old, repairing it would still make sense (pending the leak is only small).

You'll need an engineer to investigate this for you.

If your boiler is 10+ years old, and you are regularly topping up it's pressure, you should be considering buying a replacement.

New boilers are more efficient, carry long warranties and can often pay for themselves due to the savings on your energy bills.

Good reads for you:

#4 — Your gas bill is increasing without explanation 

Gas Bill Going Up Repair Boiler

Boilers have efficiency ratings, which can have a big impact on your energy bill, as well as the environment. 

Just like cars, as time goes by, older boilers become more efficient due to build up's in the system, or parts not working as they should.

This means they cost more money to run compared to modern A-rated boilers.

For comparison, modern A-rated boilers have efficiency ratings above 90%, while older G-rated models are 70% or less. 

Likely cause(s) Likely fix Cost to repair
Sludge in pipework Powerflush £200-500 
Struggling parts Service and overhaul of seals/valves £100-300


Upgrading from an old G-rated boiler to a modern A-rated boiler could save you as much as £300 a year on your bills.

Now, with Heatable, you can get a new boiler installed from £1,595, or around £20 per month.

It's a no brainer.

Good reads for you:

#5 — Replacement parts are difficult to source 

Boiler Parts Hard To Source (Repair or Replace)

The reality is that some boiler manufacturers are more well-established in the UK than others and so replacement parts are easier and cheaper to source.

So if it’s difficult to find a new boiler component and/or parts for the right price, it may be time to consider a new boiler. 

Major components such as the heat exchanger or printed circuit board (PCB) can cost several hundreds of pounds, so if your boiler is old and needs one of these replacing, it may be time to consider then it may be more cost-effective to get your boiler replaced.


This is what is considered Beyond Economical Repair (BER). 


#6 — Your boiler or radiators are making a lot of noise 

Boiler Making Noise (Repair or Replace)

Have you recently noticed any new changes in sound coming from your boiler or radiators?

Any new sounds, especially accompanied with vibrations maybe be a sign of an underlying issue. 

Over time, dirt and debris can build-up within your heating system, resulting in sludge that can cause blockages, preventing of hindering the flow of water.

This can also result in a familiar tapping sound.

Sometimes, a system cleanse such as a Powerflush can help rectify the problem. 

Other sounds, such as kettling, humming or vibrating may be a symptom of a more significant problem with your boiler or central heating system. If you do suspect a problem, it’s certainly worth consulting the help of a Gas Safe engineer. 

Likely cause(s) Likely fix Cost to repair
Sludge in pipework Powerflush £200-500 
Failing components Replacement of components £200-500 (each)


If your boiler is 10+ years old, we'd recommend a replacement boiler instead of a repair.

However, if it’s the familiar tapping sound and your boiler is less than 10 years old, it may be a blockage. 

Consult a local engineer to take a look.

Good reads for you:

#7 — Current boiler doesn’t meet hot water demands

Not Getting Enough Hot Water

If you are finding your boiler is failing to meet your hot water and heating requirements, it may be time to replace your boiler with a model with a higher power output.

If you've extended your home, or added a bathroom, more power may be reqiured.

However, if your boiler has randomly started to deliver less hot water, it sound like it could be an issue with your heat exchanger.

Likely cause(s) Likely fix Cost to repair
Boiler undersized New, more poewerful boiler £1,500-2000 
Faulty heat exchanger Replacement of component £200-600


Check out our guide on calculating the correct size boiler for your property and/or heating/hot water demands.

If your boiler is 10+ years old and is now struggling to deliver the hot water which you required, you should consider buying a new one.

Good reads for you:


Get a free, no obligation boiler quote today 

Do you think it’s time for a boiler replacement? or just curious to see how much one would cost?

Use our free boiler quote tool and we could be fitting your new boiler tomorrow.

Why choose Heatable? 

  • Gas Safe installation within 24 hours.
  • Thousands of happy customers – an average score of 4.9 on Trustpilot (that’s better than the market leader). 
  • Price match guarantee – if you find a cheaper quote, we will match (must be like for like).  
  • Multiple payment options - interest free available. 
  • 10 year guarantee. 
  • Fixed price guarantee – no hidden costs. 
  • Save your quote until later. 

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Heatable is registered in England and Wales No. 08804726 (VAT No. GB205805920 ). Trading address is 1 Station Road, Great Sankey, Warrington, Cheshire, WA5 1RH. Heatable acts as a credit broker (not as a lender) and offers credit products through a panel of lenders. Heatable is authorised and regulated by the Financial Conduct Authority (reference no. 805259).

[1] Price based on a like for like combi swap in a 2 bed, 1 bathroom terraced home with a standard flue

[*] Installation dates are subject to installer availability

[ยน] only available on combi boiler installations

Financial Support: If you are in receipt of certain benefits, you may be entitled to claim a free boiler grant.