04 / 06 Boilers & gas safety
Boiler Service
A boiler can seem to work perfectly while a seal is failing, the flue is partly blocked or it is burning gas poorly. An annual boiler service is how those problems are found before they become a breakdown or a safety risk. Our boiler servicing covers combi, system and regular gas boilers, and every gas boiler service is carried out by Gas Safe registered engineers, as the law requires.
Boiler servicing is part of our plumbing services. If you are a landlord, the legal yearly check is a different job, covered by our landlord gas safety certificates service.
- Part ofPlumbing Services
- On this page10 topics covered
- Answered here6 common questions
- FreeSurvey & itemised quote
01What is included
What Is Included in a Boiler Service?
The exact checks follow the manufacturer's service instructions for your model, but a full service normally covers:
Outside the Boiler
- Operation: The boiler is run on heating and hot water, and the controls are checked.
- The flue: The terminal outside, its clearances, and the flue route, including any section in a ceiling or boxed-in void.
- Ventilation and siting: The space around the boiler and any air vents it needs.
- Pipework: Visible gas and water connections, and the condensate pipe and its route.
Inside the Boiler
- The casing seals: The boiler casing seals the combustion chamber, so its seals are checked and replaced if damaged.
- Burner and heat exchanger: Inspected and cleaned where the manufacturer requires it.
- Condensate trap: Cleaned, as a blocked trap is a common cause of breakdowns.
- Ignition and flame detection: Electrodes checked, cleaned or adjusted.
- Safety devices: Including flame failure protection and the pressure relief valve.
Tests and Records
- Flue gas analysis: A calibrated flue gas analyser measures what the boiler is producing, to confirm it is burning gas safely and efficiently.
- Gas pressure and rate: Checked against the manufacturer's figures, with a gas tightness test where needed.
- System pressure and expansion vessel: Checked and recharged if needed.
- Service record: The results are written up, and the service record in the boiler's Benchmark checklist is completed.
02Why
Why Service Your Boiler?
- Safety: A poorly burning or leaking boiler can produce carbon monoxide, which you cannot see or smell.
- Fewer breakdowns: Worn seals, blocked traps and failing parts are found before they stop the boiler, often in the middle of winter.
- Efficiency: A clean, correctly set boiler uses less gas for the same heat.
- Warranty conditions: Most manufacturers require a yearly service to keep their warranty valid.
03How often
How Often Should a Boiler Be Serviced?
Usually every 12 months, as most manufacturers and the Gas Safe Register recommend. Booking in late spring or summer means any repairs are done before the heating season, when engineers are busiest. Other gas appliances, such as a gas fire, should be checked at the same time.
04Warranty
Does Missing a Boiler Service Void the Warranty?
It can. Most manufacturer warranties are conditional on the boiler being serviced every year by a Gas Safe registered engineer, with each service recorded in the Benchmark service record. If a service is missed, the manufacturer can refuse a claim. Check the terms that came with your boiler, and keep every service record.
05Landlord check
Boiler Service or Landlord Gas Safety Check?
| Annual boiler service | Landlord gas safety check | |
|---|---|---|
| Purpose | Keeps the boiler safe, efficient and reliable | Confirms every gas appliance, fitting and flue the landlord provides is safe |
| Required by law | No, but strongly recommended and usually a warranty condition | Yes, every year for rented homes |
| What is covered | The boiler, in depth: cleaning, parts and adjustments | Safety checks on each appliance; not a full service |
| Paperwork | Service record and Benchmark entry | Gas safety record for the tenants |
Landlords can usually have both done in the same visit. Our landlord gas safety certificates page explains the legal duties in full.
06Carbon monoxide
Carbon Monoxide Alarms and Warning Signs
We recommend an audible carbon monoxide alarm, marked to BS EN 50291, in every room with a gas appliance. Warning signs of a problem include a lazy yellow or orange flame on a gas fire or older appliance, soot or staining around it, and heavy condensation in the room. Symptoms of carbon monoxide poisoning include headaches, dizziness, sickness and breathlessness, often easing when you leave the house.
If your alarm goes off, follow our emergency boiler services guidance and call the National Gas Emergency number on 0800 111 999.
07Cost
How Much Does a Boiler Service Cost?
A boiler service is a defined job, so we give you a fixed price when you book. The price depends on:
Every factor is priced line by line after your free survey — no guesswork, staged payments.
Book a boiler service- 01
The boiler type and model, as some take longer to strip and clean.
- 02
Access
For example, a boiler in a loft or a tight cupboard.
- 03
Parts
Seals or a condensate trap that need replacing, which we tell you about before fitting.
- 04
Other appliances, such as a gas fire, or a landlord check in the same visit.
08After
What Happens If a Fault Is Found?
We explain what we found and give you the cost of any repair before carrying it out through our boiler repair service. If an appliance is unsafe, we follow the gas industry's unsafe situations procedure and, with your permission, turn it off until it is fixed.
A boiler service checks the boiler itself. If the wider system has problems, such as cold radiators, a noisy pump or low inhibitor levels, a central heating system maintenance visit or power flushing may be the answer. If the boiler is old and unreliable, we can also advise on boiler replacement.
09Areas
Boiler Servicing Across London
We carry out boiler servicing across London, with a focus on east and south-east London. Find out more on our pages for boiler servicing in London, boiler servicing in Ilford, boiler servicing in Barking, boiler servicing in Dagenham, boiler servicing in East Ham and boiler servicing in Orpington.
10FAQs
Boiler Servicing FAQs
How much does a boiler service cost?
It depends on the boiler type, access, any parts needed and whether other appliances are checked at the same visit. We give you a fixed price when you book.
How often should a boiler be serviced?
Usually every 12 months, as most manufacturers and the Gas Safe Register recommend.
What is included in a boiler service?
Checks of the flue, seals, burner, condensate trap, ignition and safety devices, a flue gas analysis, gas pressure and system pressure checks, and a written service record.
Does missing a boiler service void the warranty?
It can. Most manufacturer warranties require a yearly service by a Gas Safe registered engineer, so check your terms and keep every service record.
Is a boiler service the same as a gas safety certificate?
No. A service maintains the boiler in depth. A landlord gas safety check is a legal safety check of every gas appliance in a rented home, and both can usually be done in one visit.
Should I service a new boiler?
Yes. Most manufacturers require the first service around a year after installation to keep the warranty valid.
11Plumbing Services
Explore other boiler services
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Book Your Boiler Service
Send us the make and model of your boiler, or a photo of its data badge, and we will give you a fixed price and a date.
Send us a photo on WhatsApp to get started, or use our contact form.
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