1. Banging, gurgling or whistling. A kettle-like whistle ('kettling') usually means limescale on the heat exchanger. Banging can be a failing pump or airlocks. Neither fixes itself — both get more expensive the longer they run.
2. Pressure that keeps dropping. Topping up once a year is normal. Topping up every week means a leak somewhere — on the boiler, a radiator valve, or under a floor. We find these fast with a proper pressure test.
3. Lukewarm radiators or hot water that runs hot-and-cold. Often a diverter valve or a scaled-up plate heat exchanger. Usually a repair, not a replacement — an honest engineer will tell you which.
4. The pilot light or flame looks yellow. A healthy gas flame burns blue. Yellow or orange flames can mean incomplete combustion and carbon monoxide risk. This one isn't a wait-and-see: switch it off and call.
5. It keeps locking out. Modern boilers shut down when something's wrong rather than run unsafely. A boiler that needs resetting every few days is asking for help.
If any of these sound familiar, our emergency callout is £95.99 including the first hour — covering boilers, radiators, fires, cookers and hobs across South Devon, 24/7. And if it turns out your boiler is beyond sensible repair, new boilers start from £1,799 fully fitted.
Need a hand? Fixed prices, online booking, and a Gas Safe engineer at your door across South Devon.
Book onlineMore from the van
Why Your Boiler Needs an Annual Service (And What Happens If You Skip It)
February 2026Dripping Tap to Blocked Loo: When to DIY and When to Call a Plumber
February 2026Power Flushing: What It Is and the Signs Your Heating System Is Begging for One
January 2026Heat Pumps in South Devon: What We Fit, What We Service, and Whether One Suits Your Home