Boiler Service

What a PH247 boiler service includes

Most of a service is measurement. The readings tell you whether the boiler is burning safely and running as the manufacturer intended.

Flue gas analysis

We put an electronic analyser into the flue and read the combustion. The ratio of carbon monoxide to carbon dioxide tells us whether the burner is running correctly. A reading outside the manufacturer’s range means incomplete combustion, and incomplete combustion is how carbon monoxide gets into a property. This is the most important measurement in the whole service and it cannot be judged by eye.

Gas rate and operating pressure

We check the working pressure at the appliance and the standing pressure at the meter, then confirm the boiler is burning the right volume of gas for its rated output. An over-gassed boiler wastes money and stresses components. An under-gassed one will not heat the property properly, and it often gets misdiagnosed as a boiler that is too small.

Combustion chamber, heat exchanger and burner

We open the case, inspect the combustion chamber and clean the heat exchanger and burner where needed. Deposits on the heat exchanger reduce efficiency, and on a condensing boiler they can block the condensate route and cause a lockout later in the year.

Seals, safety devices and controls

A room sealed appliance relies on its case seals to keep combustion products out of the room, so a perished seal is a safety fault and we replace it. We check the flame supervision device, the overheat thermostat and the pressure relief valve, and we test that each one actually operates rather than assuming it does.

Expansion vessel and system pressure

A flat expansion vessel is the most common reason a boiler keeps losing pressure, and it is routinely missed. We check the charge pressure against the manufacturer’s figure and recharge it where needed, rather than topping the system up and leaving you to call again in a month.

Flue integrity and ventilation

We inspect the visible length of the flue, its terminal position and clearances, and the seals at every joint. Where a flue runs through a void, inspection hatches are required so it can be seen, and we check they are there.

Condensate and system water

We check the condensate trap and pipework, because a blocked or frozen condensate is one of the most common winter breakdowns in London. We also check the system water for debris and scale, which is what destroys heat exchangers over time. If the water is heavily contaminated we will tell you, and a power flush may be the right answer.

Your Benchmark record and your warranty

We complete and sign the Benchmark service record in your boiler’s logbook at every visit.

If the Benchmark record is not signed at each annual service, most manufacturers will refuse a warranty claim. A 10 year guarantee is worth very little if you cannot evidence the servicing behind it.

That matters most if you have a Vaillant or Baxi boiler, since both carry guarantees of up to 10 years that depend on the boiler being serviced every year and recorded properly.

Which boilers we service

We are qualified to service:

• Combination boilers
• System boilers
• Conventional boilers
• Condensing boilers
• Gas fired boilers

If your hot water comes from an electric unit or a cylinder rather than a gas boiler, see electric boiler service or hot water cylinders. If you live in a flat on a communal heating network you may have a heat interface unit instead of a boiler.

What it costs and how long it takes

A standard boiler service is £150 including VAT and takes a maximum of one hour. Payment is taken when you book. All our rates are published on our rates page.

A service is an inspection. If we find a fault we will tell you what it is and what it costs to put right before carrying out any further work. We will not do chargeable work without asking you first.

Landlords: a service and a CP12 are not the same thing

A gas safety certificate, often called a CP12, is a legal safety check required every year on each gas appliance in a rented property. It confirms the appliance is safe on the day it was checked.

A service is a maintenance visit that cleans, tests and records the condition of the boiler. A certificate does not mean the boiler has been serviced, and a service on its own does not satisfy your legal duty as a landlord. Plenty of landlords assume one covers the other. See landlord gas safety certificates.

Booking, access and cancellation

• Payment is taken when you make the booking.
• You can move the appointment free of charge up to 24 hours beforehand. Changes inside 24 hours are rechargeable.
• Cancelling with less than 24 hours notice forfeits the deposit.
• The engineer needs clear access to the boiler. If it cannot be reached, the visit ends there and a return visit is chargeable, so please clear the cupboard before we arrive.
• If you need an arrival time on the day, call the office on 020 3764 2713.

Once you book, we send you our terms and a customer help manual setting out how we work.

After the service

The engineer will talk you through what was done and flag anything that needs attention, with no pressure to book it there and then. Your certificate is emailed to you electronically.

If you would rather not think about it each year, our service plans and proactive maintenance cover the annual visit automatically.

Related services

We also handle boiler repair, boiler installation, gas safety certificates and power flush across London.

See also proactive maintenance.