How often should a boiler be serviced by law?

A boiler service will ensure your central heating system is running safely and efficiently. We tell you how frequently a check is required and if it is a legal requirement

Just as a car needs servicing to keep it driving smoothly, a boiler service is an important maintenance task to keep the engine of your home operating well. But, how often should a boiler be serviced to keep it safe and efficient? And, is it a homeowners responsibility required by law? We ask the experts.

How often should a boiler be serviced?

How often your boiler should be serviced by law depends on your living arrangements. However, routine servicing will keep your appliance safe, save you money and keep your warranty valid.

Boiler service requirements for homeowners

If you are the home owner, it's not a legal requirement to have a boiler service. However, it's an annual maintenance task that if overlooked could end up leaving you in the cold and out of pocket in the long run. Or, worse still, neglecting the task may lead to having to replace a boiler completely. 

'In order to keep your boiler working as effectively as possible, it is important to book in regular boiler services' advises Martyn Bridges, Head of Technical Communication and Product Management at Worcester Bosch. 'An unserviced boiler could lead to faults, higher energy bills and your warranty ending early.'

kitchen room with white boiler on white wall

(Image credit: Worcester Bosch)

Boiler service requirements for tenants

Landlords are required by law to have gas appliances in rental properties checked for safety. As stated on the Gas Safe Register (opens in new tab), under The Gas Safety (Installation and Use) Regulations 1998 (GSIUR), it is outlined that duty of care as a landlord is to ensure all gas appliances, fittings, chimneys and flues are safe and working efficiently.

This includes a boiler check for gas safety. The assessment, required by law is carried out between 10-12 months after the last completed check. On completion, tenants will be issued a Gas Safety record. Remember, a gas safety check may not include a full service.

'I recommend tenants check their private landlord agreement. A boiler service may not be included within the Gas Safety Check level of cover the landlord owns,' says Paul Sturgess, Voids Contractor for WestKent. 'However, as central heating systems advance in technology, a boiler service is usually required as part of the safety check to establish the Gas Safety Certificate valid.'

Why have a boiler service?

An annual boiler service will ensure it's running efficiently and safely to keep your home at the perfect temperature. Regular maintenance will minimise the risk of breakdowns and lengthen the appliance lifespan.

  1. Safety– All devices that burn wood or fossil fuels such as natural gas could produce carbon monoxide (CO) if they are faulty. The gas is odourless, colourless and tasteless so can easily go undetected. It is vital to test your boiler regularly by a Gas Safe registered engineer to keep your home safe and your family in good health.
  2. Warranty – Although it's not a legal requirement, an annual boiler service may be a manufacturer's condition to maintain a boiler's certificate of guarantee. 'Some warranties require annual servicing to remain valid, so it's worth checking your warranty details,' explains a spokesperson from Worcester Bosch. It is the owner's responsibility to book any service appointments within the warranty period.
  3. Energy efficiency – A maintained and regularly serviced boiler will work to ensure your appliance is running with optimum energy efficiency and will prolong the lifespan of the boiler.
  4. Cost efficiency –  The cost of maintaining a boiler regularly can be significantly less than the cost of breakdown repairs or replacement boilers. Boiler service companies and energy suppliers usually offer options to spread the cost making the agreement less of a dent on your bank balance.
  5. Fault finding – If a broken boiler during winter months sounds like a nightmare situation, an annual boiler service should put your mind at ease. During a service, a gas engineer will identify and fix any foreseeable problems before they occur.

room with white boiler and shelves on white walls

(Image credit: BOXT)

What does a boiler service entail?

A boiler service can vary slightly from company to company depending on the boiler manufacturer and model. However, the general service checklist conducted by Homeserve (opens in new tab) includes:

  • Visual inspection - checking the boiler is clean and identify any signs of distress.
  • Operation control - testing controls and safety devices for operation. 
  • Flue and combustion release - making sure any obstructions in the pipe are cleared and fittings are made secure from the boiler to exit point.
  • Cleaning components - inspecting and cleaning main components including the main burner, heat exchanger, flue ways and ignition pins. 

Who should conduct my boiler service?

A heating engineer who works on gas boilers will need to be on the Gas Safe Register list. If you own an oil fuelled appliance, turn to Oil Firing Technical Association (OFTEC) registered engineers. For bio and solid fuel boilers, source an engineer who is Heating Equipment Testing and Approvals Scheme (HETAS) qualified.

'For peace of mind the engineer must carry a Gas Safe Register ID card,' says a spokesperson at Worcester Bosch. 'Ask to see identification as soon as your engineer arrives.'

  1. Manufacturers – Most boiler manufacturers employ contractors with all of the above qualifications. They usually offer a subscription cover package that includes callouts, parts and labour costs and annual boiler service.
  2. Energy suppliers – Another option is to book an annual boiler service via your registered energy supplier. Household names such as British Gas, Scottish Power, EDF and E-ON have online services and apps to book home care cover deals.
  3. Online boiler companies – Online boiler companies such as Boxt and Heatable are a relatively new and cost-effective concept. They too offer competitive monthly subscription service plans and Gas Safety certificates.
  4. Independent Gas Safe Engineers – Alternatively, independent contractors who are IPHE (Chartered Institute of Plumbing and Heating Engineering) registered heating engineers can be found on Checkatrade (opens in new tab). They offer a conditional 12-month guarantee after service.

room with white boiler on wooden cupboard

(Image credit: Future PLC/ Colin Poole)

Boiler service checklist

There will also be a series of tests to carry out during a service checklist inspection and these include:

  • Flame sense device and whether it operates correctly
  • Pilot burner and any cables and probes
  • High-limit thermostat
  • Boiler operation
  • Provision of adequate ventilation
  • Flue effectiveness
  • Heating controls
  • Electrical wiring connections
  • Location of the boiler and nearby combustible materials
  • Gas and pressure flow
  • Safety devices
  • Seals.

At the end of the boiler service, the engineer will ensure the boiler is running smoothly. The engineer will issue a record of boiler pressure and heat inputs. A boiler service should last at least 30 minutes depending on the brand and age of the model.

Rachel Homer

Rachel Homer has been in the interiors publishing industry for over 15 years. Starting as a Style Assistant on Inspirations Magazine, she has since worked for some of the UK’s leading interiors magazines and websites. After starting a family, she moved from being a content editor at Idealhome.co.uk to be a digital freelancer and hasn’t looked back.