The decision between repairing and replacing a boiler often comes down to cost. Short-term savings can turn into long-term expenses if you make the wrong choice. Knowing when to patch up a failing system and when to cut your losses is key. A quick fix might seem cheaper today, but constant breakdowns will soon drain your wallet and patience.
Typical Boiler Repair Costs
Most boiler repairs fall between £100 and £500, depending on what’s gone wrong. Simple faults, like a stuck thermostat or a pressure drop, can often be fixed for under £150. Bigger problems, such as a damaged heat exchanger, PCB failure, or a leaking pump, push costs much higher. Some components alone can cost several hundred pounds, and labour adds even more. Older boilers are harder to fix. Parts can be scarce. Labour takes longer. And in many cases, there’s no guarantee it’ll keep running for long after. If you’ve had more than one major repair in the last 18 months, it’s a sign that problems lie ahead.
Cost of Replacing a Boiler
A new boiler installation starts from around £1,800, rising to over £3,500. It depends on the type of boiler, brand, and complexity of the installation. That includes parts, labour, and disposal of the old unit. A new combi boiler tends to be the cheapest and quickest to install, while system or conventional boilers often need more pipework. It’s a bigger upfront cost. Modern boilers run at over 90% efficiency, compared to older models, which often sit below 70%. That difference adds up. You’ll see the savings in your heating bill within the first year. Most new boilers also come with a 7–10 year warranty. That’s years of peace of mind, where servicing is the only cost, usually around £100 per year.
When Repair Makes Sense
- The boiler is less than 8 years old
- Parts are readily available
- The issue is minor or the first problem you’ve had
- Total repair cost is under £300
If your boiler has been running reliably until now, and the fault is quick to fix, repair it. Ensure the engineer checks for other wear and tear while they’re working.
When to Replace Instead of Repair
- The boiler is 10 years old or more
- Repairs are becoming frequent
- Engineer flags multiple faults
- Efficiency is dropping, and heating bills are rising
- Parts are obsolete or hard to find
At this point, repair becomes a short-term patch. It might work now, but it probably won’t last. Spending £400 to fix an old boiler when a new one costs £2,000 doesn’t make sense if you’ll need to replace it next year anyway.
Long-Term Value
A replacement often works out cheaper in the long run. New boilers need fewer repairs. They use less gas. They heat faster. You also reduce the chance of carbon monoxide leaks and gain controls, which help you manage energy use more efficiently. If your current boiler runs loudly, takes a long time to heat, or loses pressure, replacing it will solve the problem.
Speak to a Qualified Engineer
Always speak to a Gas Safe registered engineer. Get a quote for both options. Ask what they’d do if it were their own home. If they recommend a new system, check what’s included, flush, controls, warranty, and aftercare. For help comparing options, speak to a new boiler installation expert who can assess your system and recommend what makes the most financial sense.
Conclusion
Repairing might look cheaper today. If the boiler’s ageing, the fix is expensive, and you’ve already had issues, replace it. You’ll save more in the long term and avoid the stress of constant breakdowns. Make a smart call based on age, efficiency, fault history and repair cost. Not just the price on the invoice.
