Annual servicing is cheap relative to what it protects: the manufacturer warranty, the appliance's lifespan and the safety of everyone in the property. It is also the area where quality varies most, because a fast visual glance and a full service look identical on an invoice.
Here is what a proper service covers, and how to check yours did.
What a full service includes
- Combustion analysis with a calibrated flue gas analyser, with readings recorded.
- Case removal and inspection of the burner, heat exchanger and condensate trap.
- Seals, electrodes and ignition components checked and cleaned or replaced.
- Flue integrity and terminal position checked, including any voids the flue passes through.
- Gas rate and operating pressure checked against the manufacturer's data.
- System side: pressure, expansion vessel charge, inhibitor level and filter condition.
- A written service record with the readings on it — not just a sticker.
How to tell a real service happened
Ask for the combustion readings. If the case was never removed and no analyser was used, the appliance was not serviced — it was looked at. On modern condensing boilers the heat exchanger and trap are exactly where problems accumulate, and neither is visible with the case on.
What it costs and why it varies
A standard gas boiler service is a modest fixed cost; oil boiler servicing typically costs more because it includes nozzle replacement, combustion setup and filter changes. Landlord gas safety certificates are priced separately, and combining the CP12 with a service in the same visit is usually the economical route for rental properties.
Rural travel, multiple appliances and older non-standard equipment can affect the figure, and we say so at booking rather than on the invoice.
The warranty consequence
Manufacturers make extended warranties conditional on documented annual servicing. Miss a year and a claim can be refused, which turns a small saving into a large exposure — particularly on appliances carrying ten- and twelve-year cover. Keep the service records; they are the evidence.
Frequently asked questions
- Is a service the same as a gas safety certificate?
- No. A CP12 is a landlord safety inspection of gas appliances; a service is maintenance of a specific appliance. Many landlords sensibly book both together, but they are separate pieces of work.
- How long should a service take?
- Typically 45 minutes to an hour and a half for a domestic gas boiler, longer for oil. Anything much under half an hour is unlikely to have included case removal and combustion analysis.
- Do I need one if the boiler is working fine?
- Yes. Servicing catches the things that are not yet symptoms — seal degradation, a filling expansion vessel, low inhibitor — and keeps the warranty live.
- Do you send reminders?
- We do, so services and landlord certificates do not lapse by accident.
Book a service that includes the readings
Tell us the make, model and last service date and we will confirm the price up front.