Getting the best boiler service
An annual boiler service is essential for keeping your boiler running smoothly and safely.
Our 2020 boiler reliability survey of 7,500 boiler owners found that about two-thirds of boilers that are serviced annually have never needed a repair.
So spending a bit of money on a boiler service could potentially spare you a huge repair cost in the future, as well as giving you piece of mind.
Read on to find out what you can do to ensure you get the best boiler service. We'll also tell you how much you should expect to pay for a boiler service so you don't get overcharged.
How much does a boiler service cost?
There are two types of boiler service schemes: an annual boiler cover package or a one-off service.
A one-off service should cost from £60 - £100 for a gas boiler, and a little less on average for an electric boiler.
A boiler cover package typically costs £200 - £300 a year and should include an annual service and cover repair costs. The average Which? member pays £288 per year for a boiler cover package.
Which is cheaper: one-off service or boiler cover?
You'll probably save money if you pay for services and repairs as you go along, rather than take out boiler cover - where you pay a monthly fee that also covers repairs.
Our analysis shows that for more than nine out of ten Which? members this was more expensive than paying for one-offs.
Some home insurance companies also gives you cover for boiler breakdowns, either as standard or as an optional extra, so it's worth checking if you already have this. The cost of adding breakdown cover to an insurance policy is usually much less than getting a breakdown contract, but you don't get the same benefits.
Boiler service checklist
It is important that you get your money's worth from a service, after all the purpose of it is to prevent your boiler breaking and costing you more in the long run.
Here's what should take place as part of a boiler service:
- A visual check of the boiler and flame, if possible
- Checks on the flue (externally and internally)
- Checking the operating pressure and/or heat input
- Checking safety devices
- Check case seals for an effective seal
- Boiler casing removed to check all main boiler components (burner, heat exchanger, main injector, spark/sensor probe)
- Boiler fired safely to identify any working faults
- Boiler parts cleaned, if necessary
- A service report showing everything the engineer has done
You should get your boiler serviced every year by a . You can arrange a service yourself or through a heating engineer – it should cost about £72. Alternatively, you can get boiler cover through a plan, such as Homecare, that includes a boiler service, but this can cost more than £200.
Boiler service tips
Ask what will be included in the boiler service. Watch the engineer and use our checklist to ensure that they cover the basics. A good boiler service should last at least 30 minutes. If it’s shorter than this, ask why.
Finally, ask for a written report and check it is accurately filled out. If you have any concerns, contact the Gas Safe Register on 0800 408 5500 or through their . It's also worth getting a to be safe.
Before paying for repairs, check whether your boiler is still under its initial warranty. Most new boilers typically come with cover for parts and labour in the first one or two years.
Although the checklist should stand you in good stead for most boilers, bear in mind that not all boilers are the same.
Most older conventional systems, for example, have parts such as the heat exchanger, burner and fan that would need to be dismantled and checked. This is not normally necessary for a modern boiler, unless the flue gas analysis suggests there's a problem.
Boiler servicing results by firm
If you opt for ‘central heating response plus’ cover with the AA, you'll be entitled to an annual service per membership period. An engineer will do an initial inspection and service within 42 days of taking out the cover and then you'll be contacted when the second service is due.
The service includes:
- boiler combustion test
- visual inspection of flue route and termination
- checking for water leaks, signs of heat stress and mechanical deterioration
- checking pipe work and ventilation
- carrying out a leak detection check
- the disassembly and cleaning of key components where they are found to be not performing to the manufacturer’s recommended specification.
The annual service does not include the following:
- removal of sludge or hard-water scale from the main heating system
- chemical flush.
Length of service: 30 minutes
Cost: The AA is no longer providing quotes for boiler and home cover to new customers.
British Gas offers a one-off boiler service starting from £85 around £79 or you can sign up to one of the four , all of which include an annual service. The cost of both will depend on factors such as water hardness and property type.
Once a deal is agreed and you receive a quote your service will include:
- Check your boiler for corrosion and leaks.
- Clean its parts as required
- Remove your boiler casing to check its main components are working
- Put the casing back on and make sure it’s properly sealed
- Check the gas pressure to make sure it’s at the right level
- Do a flue test to check that there are no unsafe emissions coming from your boiler
At the end of the visit, their engineer will leave a checklist with you including all the relevant safety information for your boiler. Neither services cover repairs to your gas boiler.
Length of service: 17 minutes
Cost: Starting from £85 for a one-off service or from around £170 (£60 excess) or £230 (£0 excess) for an annual contract
As part of its HomePlan cover, Corgi offers basic boiler and central heating system repairs and an annual boiler service with its . A boiler service is also included in more expensive packages, too. The service includes:
- a visual check of the boiler
- the boiler being fired safely to identify any working faults
- a flue gas analysis efficiency test
- opening up the boiler and inspecting it, if necessary
- checking the flue and ventilation are in accordance with Gas Safety (Installation and Use) Regulations
- checking and adjusting the system pressure
- cleaning the condensate trap
- visually checking and bleeding radiators, if necessary
- a visual check of the hot water cylinder
- confirmation in writing that the service has been carried out.
If your boiler is over seven years old when you take out the cover, the monthly premium will increase by up to £2.
Length of service: 45 minutes
Cost: From £156 (£60 excess) or £216 (£0 excess) for an annual contract
HomeServe offers one-off boiler servicing from around £84. Its service includes:
- boiler inspection to make sure it’s working properly
- cleaning the parts if needed
- checking that all the seals and gaskets are secure
- making sure it’s not emitting any unsafe fumes
- testing the gas connections and gas pressure
- visually checking any other gas appliances.
Appointments are booked in four-hourly windows and can be made via the website. HomeServe doesn’t service or repair Promox, Powermax, Ferroli, Keston or Gledhill boilers.
Length of service: 45 minutes
Cost: £84 for a one-off service or from £210 (£100 excess) or £258 (£60 excess) for an annual contract
To receive an annual boiler service with Scottish Power you’ll need to sign up to its , which costs from £126 per year. Other features in the plan include ongoing maintenance, a 24/7 UK-based helpline and a replacement boiler worth up to £750, if required.
Insurance packages do not include an annual service.
Length of service: 38 minutes
Cost: From £126 (with a £99 call out fee) or £252 (with a £0 call out fee) for an annual contract
For a fixed-price of £90, SSE will send out a Gas Safe registered engineer to service your boiler. If there are repairs needed the engineer can offer you a quote to fix it and you'll be provided with a report at the end.
If anything goes wrong within 21 days of the call-out, an engineer will come out free of charge. If the problem is a result of the service it will also be repaired for free.
Length of service: One hour
Cost: £90 for a one-off service, from around £245 for an annual contract
The cost and length of an independent boiler service will vary depending on the age and model of your boiler, the area in which you live, who carries out the service and the time of year, so always seek a handful of quotes and make sure the engineer is Gas Safe registered.
Length of service: Between 25 minutes and one hour
Cost: Between £60 and over £100 for a one-off service