We get asked this constantly, usually phrased as "it's 15 years old, is it even worth fixing?" The honest answer is: age is one input, not the deciding one. We've kept 18-year-old boilers running reliably for years after a single sensible repair, and we've seen 8-year-old boilers where replacement was clearly the better call.
What age actually tells you
Mainly, it tells you about parts availability and efficiency, not reliability on its own. Older, discontinued models can have longer waits for specific parts, or in some cases parts are no longer manufactured at all — that's the point where age becomes a genuine practical constraint rather than just a number.
What matters more than age
- What's actually broken. A pump, valve or PCB fault on an old-but-sound boiler is usually a perfectly good repair. A cracked heat exchanger on the same boiler is a different conversation.
- How often you're calling someone out. One repair in ten years tells you very little. Three in the last eighteen months tells you the boiler's becoming unreliable, regardless of its age.
- Running costs. A 15-year-old boiler is almost certainly less efficient than a current model — that's a genuine ongoing cost even when nothing's actively broken.
A practical way to think about it
If a repair is going to cost a small fraction of a new boiler and there's no pattern of repeat faults, repairing is usually the sensible move — old doesn't mean done. If you're weighing a costly repair against replacement, our full repair vs. replace guide walks through the wider decision, and our cost guide has real figures for both sides.