Boiler servicing

Boiler servicing in Surrey: what a proper service involves

Why fifteen minutes is not a service

There is an enormous difference between a visual check and a service. A visual check confirms the boiler lights and produces heat. A service measures whether it is burning correctly, whether the safety devices operate, and whether anything is degrading before it fails.

A genuine service on a typical domestic boiler takes around an hour. If somebody is in and out in fifteen minutes with a sticker, you have paid for a sticker.

What we measure, and why each one matters

Gas rate. We measure the actual gas consumption against the manufacturer's stated figure. A boiler running rich wastes fuel and produces more carbon monoxide; running lean it may not reach output and can suffer flame instability.

Flue gas analysis. A calibrated analyser samples the products of combustion and reports the ratio of carbon monoxide to carbon dioxide. This single reading tells us more about combustion health than anything else, and it is the only way to know the burner is behaving.

Flue integrity, inside and out. We check the seals, the terminal, and where possible the run. A degraded flue seal can allow products of combustion into the property, which is the failure mode that actually kills people.

Heat exchanger condition. Inspected and cleaned. Fouling reduces heat transfer, raises flue gas temperature and gradually pushes the boiler out of condensing mode.

Burner and injectors. Examined for corrosion and deposits, and cleaned where required.

Gas soundness. Every joint and seal tested for leakage.

Safety devices. Overheat cut-offs, flame supervision and any pressure switches operated and confirmed working.

Expansion vessel. Pressure checked and recharged. A flat vessel is the most common cause of a system that loses pressure repeatedly, and it is routinely missed.

Condensate trap. Cleared. A blocked trap is the most frequent cause of a boiler locking out in the first cold snap.

System pressure and controls. Set correctly and demonstrated to you.

You get the actual readings recorded, not a date on a sticker. That record is what makes next year's service a comparison rather than a guess, and it is what a manufacturer will ask for if you ever claim on the guarantee.

Landlord gas safety certificates

If you let residential property, the Gas Safety (Installation and Use) Regulations require an annual safety check on every gas appliance and flue in the property, carried out by a Gas Safe registered engineer. You must give a copy of the record to existing tenants within 28 days, and to new tenants before they move in.

The check and a service are not the same thing. A safety check confirms the appliance is safe. A service goes further and maintains it. Doing both on one visit costs less than doing them separately and keeps the appliance reliable rather than merely legal.

Records must be kept for two years. Penalties for non-compliance are serious, and in the event of an incident the absence of a record is the first thing that will be examined. We arrange access with tenants directly, which is the part letting agents find most useful, and email certificates through the same day.

Carbon monoxide: the reason any of this exists

Carbon monoxide has no colour, no smell and no taste. Symptoms resemble flu — headache, nausea, dizziness, tiredness — which is exactly why it is so dangerous: people assume they are unwell rather than being poisoned.

Warning signs on an appliance include a lazy yellow or orange flame where it should be crisp and blue, black or sooty marks around the casing, a pilot light that repeatedly goes out, and excessive condensation in the room. If you notice any of these, stop using the appliance.

An audible carbon monoxide alarm to BS EN 50291 should be fitted in any room with a fuel-burning appliance. They cost very little. If you smell gas, ring the National Gas Emergency Service on 0800 111 999 immediately — it is free and operates 24 hours.

When to service, and what it saves

Annually, and ideally in late summer or early autumn rather than December. Two reasons: engineers are less stretched so you get a date that suits you, and a fault found in September is an inconvenience while the same fault in January is an emergency with nobody available.

The financial case is straightforward. A service costs less than a single call-out. A neglected system loses efficiency gradually — a fouled heat exchanger and a sludged system can add a noticeable amount to a winter's gas bill. And the guarantee point is decisive: almost every manufacturer requires documented annual servicing, so one missed year can convert a free warranty repair into a bill running into four figures.