Fixed prices · Gas Safe registered
Boiler Service in South London
A boiler service is the cheapest job we do that saves you money. It keeps your manufacturer warranty valid, catches the perished seal or tired expansion vessel before it becomes a January breakdown, and takes about an hour. Our Gas Safe registered engineers service combination, conventional and system boilers across South London at a fixed price agreed before we arrive.
We offer two levels, and we'll tell you honestly which one your boiler needs. The basic service at £120 is the full annual safety and performance check most boilers want each year. The full service at £220 strips and cleans the main heat exchanger, replaces the seals and electrodes and uses genuine manufacturers parts throughout - worth it on older boilers, hard-water systems and anything that has been neglected for a few years.
Boiler Service prices
Basic service
£120
- All safety checks
- Gas tightness test
- Flue gas analyser
- Controls check and system
- Condensate trap clean
- Magnetic filter cleaned
- Expansion vessel checked & recharged
- Service record filled and supplied digital
Full service
£220
All of the above, plus:
- Main heat exchanger fully stripped and cleaned
- Replaced seals
- Replaced electrodes
- All genuine manufacturers parts
Every price on this page includes VAT - what you see is what you pay. Both levels are a full service by a Gas Safe registered engineer; the difference is how deep we go. If your boiler only needs the basic service, we'll say so rather than sell you the bigger one.
Certificates & other appliances
Landlords get certificates emailed the same day. Booking a certificate and a service on one visit saves you a second appointment.
Landlord Gas Safety Certificate (CP12)
£80
- Safety check on the boiler
- Safety check on the hob or cooker
- Each additional appliance £30
- Certificate supplied the same day
Basic service added to a CP12 visit
£100
Both jobs on one visit - £180 in total, instead of £200 booked separately.
Full service added to a CP12 visit
£200
Both jobs on one visit - £280 in total, instead of £300 booked separately.
Gas fire service
£110
Natural gas fires. £85 when carried out alongside a boiler service.
What we check on every service
Gas tightness test
We test the gas installation for leaks before anything else. It is the check that matters most and the one a twenty-minute visit tends to skip.
Flue gas analysis
An electronic analyser reads the combustion at the flue. The numbers tell us whether the boiler is burning cleanly and safely, and they go on your record.
Controls & system pressure
Thermostat, timer and boiler controls tested, and the system re-pressurised properly rather than just topped up and left.
Condensate trap cleaned
A blocked trap is a common cause of lockouts. Cleaning it during a service is a couple of minutes; a frozen or blocked condensate in January is a call-out.
Magnetic filter cleaned
The filter catches the sludge that would otherwise sit in your heat exchanger. Emptying it is part of every service we do - a lot of cheaper services leave it full.
Expansion vessel checked
A flat vessel is the usual reason a boiler keeps losing pressure. We check the charge and recharge it - the fix most services quietly ignore.
Written service record
You get a record of what was checked and the combustion readings. That is what keeps a manufacturer warranty valid if you ever need to claim.
How a service works
Step 1
Book a time that suits
Pick basic or full when you book. A service takes about an hour, and we give you a real time slot rather than an all-day window.
Step 2
We protect the area first
Dust sheets down before the casing comes off. Servicing a boiler is dirty work and it should not leave a mark on your kitchen.
Step 3
Checks, clean and test
Safety checks first, then the clean, then the boiler is fired up and the combustion re-read to confirm it is running properly afterwards.
Step 4
Your record, and an honest verdict
You get the service record, and if we spot something starting to fail we tell you now with a price - not as a surprise next winter.
Boiler Service questions, answered
How long does a boiler service take?
A basic service takes about an hour for a standard combi boiler. A full service takes longer - usually 90 minutes to two hours - because the boiler is stripped down for an internal clean and reassembled. If a boiler has not been serviced for several years it can take longer again, but the price does not change.
What does a boiler service include?
Our basic service covers all safety checks, a gas tightness test, a flue gas analyser reading, a controls and system check, the condensate trap cleaned, the magnetic filter cleaned, the expansion vessel checked and recharged, and a digital service record filled in and supplied. The full service adds everything above plus the main heat exchanger fully stripped and cleaned, replaced seals, replaced electrodes and all genuine manufacturers parts.
What is the difference between a basic and a full service?
Both are a proper service by a Gas Safe registered engineer - the difference is depth. The basic service at £120 checks and tests everything and cleans the condensate trap and magnetic filter. The full service at £220 goes further and strips and cleans the main heat exchanger itself, replaces the seals and electrodes and uses genuine manufacturers parts. The heat exchanger is the part that actually furs up, so on an older or neglected boiler that is where the difference in performance comes from. Most boilers serviced every year only need the basic.
How much is a boiler service in London?
Ours is £120 for a basic service and £220 for a full service, fixed, agreed before we arrive and including VAT - several London firms quote £120 plus VAT, which is £144 by the time you pay. You will also see cheaper adverts, but a £99 service is usually a short visual check; ask whoever quotes it whether it includes a flue gas analysis, a magnetic filter clean and an expansion vessel recharge.
How often should I get my boiler serviced in the UK?
Once a year is the standard, and it is what almost every manufacturer requires to keep a warranty valid. Landlords have a separate legal duty: a gas safety check on every appliance every 12 months under the Gas Safety (Installation and Use) Regulations, which is the CP12. Servicing itself is not a legal requirement for owner-occupiers, but leaving it much beyond a year is how small faults turn into winter breakdowns.
Can I service my own boiler?
In practice, no. Topping up pressure and bleeding radiators are fine to do yourself, but a service means working on the gas appliance itself, and anyone doing that has to be competent under the gas regulations - which in reality means Gas Safe registered. It is also a practical problem: a proper service needs a calibrated flue gas analyser, and your manufacturer warranty will want a registered engineer's service record, not your own.
Do I really need an annual boiler service?
If your boiler is under manufacturer warranty then yes - almost every warranty requires an annual service by a Gas Safe registered engineer, and a missed year can void it. Beyond the warranty it is simply cheaper than a breakdown: most of the winter no-heat calls we attend are failures a service would have caught.
Can you do a gas safety certificate at the same time?
Yes, and for most landlords it is the sensible way to do it. A CP12 landlord gas safety certificate is £80 on its own. Adding a basic service to the same visit is £100, so both together are £180; adding a full service is £200, making £280 for both. That is a little cheaper than booking them separately, but the real saving is the second appointment you don't have to arrange - one engineer, one visit, one set of paperwork. Certificates are supplied the same day and extra appliances are £30 each.
More questions? Read our full FAQ or call us — we're happy to give advice over the phone.
Related services: Boiler Repair · Boiler Installation
Available across: Battersea · Putney · Balham · Tooting · Wandsworth · Clapham · Streatham · Wimbledon · Colliers Wood · Morden · Dulwich · Croydon · Thornton Heath · Norbury · Sutton · Mitcham · Carshalton · Wallington · All areas we cover
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Fixed prices agreed before any work starts — book online with the card above, or talk it through first.