Ask any Gas Safe engineer in Kent how often a boiler should be serviced and you will get the same answer: once a year. It is not a marketing line — the annual check is what most manufacturers require to keep the warranty valid, and it is the cheapest way to catch small problems before they turn into a cold house at 5 a.m. in December.
What actually happens in a boiler service
A proper annual service is not just a visual glance. On a domestic gas combi in a Maidstone kitchen it typically covers:
- Casing off, burner and combustion chamber inspected and cleaned as needed.
- Flue gases analysed (FGA) — CO, CO2 and ratio checked against manufacturer figures.
- Gas pressure verified at the appliance.
- Expansion vessel pressure checked and re-charged if low.
- Safety devices — flame supervision, PRV, condensate trap — tested.
- System pressure and any visible leaks checked.
- Benchmark log completed and signed off. Digital copy emailed.
Why once a year
Two reasons: warranty and safety. Warranty terms on Vaillant, Worcester Bosch and Ideal boilers require an annual service by a Gas Safe engineer to stay in force. Miss one, and a £2,500 replacement part can suddenly become your problem instead of the manufacturer's.
The safety side is less dramatic than headlines suggest — but combustion problems, blocked condensates and slow gas leaks all show up cheaply on a service and expensively on a callout.
Landlords — a note on CP12
A gas safety inspection (CP12) is a legal requirement for landlords in England every 12 months. It is not the same as a service — it checks the appliance is safe to operate but does not clean the internals or preserve warranty. Many Maidstone landlords book both at the same visit to save on the callout. If that is you, see the CP12 page.
Signs your service is overdue
- Boiler cycling on and off frequently, or not reaching pressure.
- Rumbling or kettling noises when heating kicks in.
- Yellow flame instead of blue on models with a viewing window.
- Water dripping or staining below the boiler.
- Radiators taking longer to warm up than they used to.
Booking a service in Maidstone
We do annual services across ME, TN and CT postcodes. Book by phone, WhatsApp or via the boiler service page. If it has been more than a year, do it before autumn — every October the callout list fills up fast.
