There’s no date stamped on a boiler that says it’s time. Some keep going happily for 20 years, others are on their last legs at 10. But most boilers last somewhere between 10 and 15 years with a service every year, and after that every breakdown is a bigger gamble. If yours is getting on, keeps letting you down or the engineer is struggling to get parts, it’s usually time to start thinking about a replacement. We see plenty of tired boilers in homes around Bristol and Bath, and you can see how we handle it on our boiler installations page. Here’s how to tell whether to repair yours or replace it.
How long should a boiler last?
With proper installation and a service every year, 10 to 15 years is a fair expectation for a modern gas boiler. Lots go on longer.
What shortens a boiler’s life is nearly always the same few things. No annual service. A dirty system full of sludge with no magnetic filter. Hard water scaling up a combi. And being the wrong size, so it’s constantly switching on and off.
Signs your boiler is on the way out
You’ll usually get some warning. Look out for:
- callouts becoming a regular thing, especially in winter
- parts that are getting hard to find, or a model that’s no longer made
- your gas bills going up while you’re using the heating the same as before
- banging, kettling or whistling that keeps coming back
- radiators taking longer to warm up
- a yellow or orange flame instead of a blue one, if you can see it
That last one needs an engineer straight away. A lazy, yellow flame can mean the boiler isn’t burning properly, and that’s a carbon monoxide risk.
Repair or replace?
This is the question we get asked most often when a boiler breaks down. There’s no one answer, but here’s how we think it through with customers.
How old is it?
Under 8 years, it’s almost always worth repairing. It may even still be under guarantee. Over 15, a big repair is often money down the drain, because something else will go next.
What’s the repair going to cost?
If a repair costs a big chunk of what a new boiler would cost, and the boiler’s past 10 years old, a replacement usually makes more sense.
Can you get the parts?
Older boilers can get harder to fix. When a part’s discontinued, it can mean a long wait or no fix at all.
How efficient is it?
If you’ve still got an old non-condensing boiler, a new one will cut your gas bills noticeably. If yours is a 10-year-old condensing boiler, the saving’s smaller and reliability is the main reason to change.
Can you get cover for a 20-year-old boiler?
It can be harder. Many breakdown cover and care plan providers have age limits, or they’ll exclude a boiler that’s found to be in poor condition when they first inspect it. Some will cover the labour but not parts that are no longer made.
So if your boiler’s 20 years old and you’re relying on cover to bail you out, read the small print carefully. Often the money’s better spent putting towards a replacement.
Do I need to replace my radiators too?
Not necessarily. Plenty of radiators last well beyond the boiler. If yours are heating evenly, aren’t leaking and are big enough for the room, they can stay.
It’s worth changing them if they’re rusting through, cold at the bottom from years of sludge, or too small to heat the room properly. Either way, the system should be properly cleaned before a new boiler goes on, and a magnetic filter fitted to protect it.
Replacing a boiler in Bristol and Bath homes
Round here, we see a lot of boilers that have quietly carried on far longer than they should have. Old floor-standing boilers in Bath basements. Back boilers behind gas fires in 1960s Bristol semis. Combis in rented flats that haven’t been serviced in years.
If you’re selling up, the age of the boiler can come up in a survey too. We’ve covered that in should I replace an old boiler before selling my house.
Frequently asked questions
Is it cheaper to repair or replace a boiler?
In the short term, a repair is almost always cheaper. Over a few years, it depends. If the boiler is old and needs one repair after another, those bills add up and you still end up replacing it. For an idea of what a new one costs, see how much does a new boiler cost.
Should I wait for my boiler to break before replacing it?
You can, but we wouldn’t. If it breaks in winter, you’re without heat while you get quotes and wait for an installation slot. Replacing it before it fails lets you choose the date, compare prices and avoid a cold week.
Will a new boiler save me money?
If you’re replacing an old non-condensing boiler, yes, and you’ll notice it on your gas bill. If your current boiler is a condensing one, the saving’s smaller. Either way, you’ll have fewer repairs and a new guarantee, which is worth a lot on its own.
Not sure whether to repair or replace?
Give us a ring on 01275 400 687 or send us a message. We’ll look at your boiler and give you an honest view, even if that means keeping the one you’ve got.