Whether you have a combi boiler or conventional one, no matter if it’s an oil-fired system or a gas-powered boiler, they all need a little care to keep heating your home and water problem-free. Regular safety checks can help keep things ticking along nicely and prevent the need for emergency repairs. Find out more about all of this with our guide to your annual boiler service.

What is a boiler service?

A boiler service is a manual inspection conducted by a plumber or engineer. They will inspect your boiler for any potential faults or issues and service particular parts within it, helping to catch any problems before they result in a major break down or could pose a potential safety risk.

It’s worth noting that most new boilers come with a manufacturer’s warranty but in most cases, in order for it to be valid, you will need to have your boiler serviced every 12 months.

One of the best ways to ensure your boiler works effectively and efficiently is to book an annual boiler service with a qualified engineer.

Who can service a boiler?

You can book a plumber or boiler specialist to inspect your boiler, but it’s vital, if you have a gas-powered system, that they’re Gas Safe registered.

An engineer who is not appropriately qualified working on a boiler is both illegal and dangerous If you’re unsure, you can ask to see the engineer’s Gas Safe Card which will say if they’re qualified to carry out the gas job you’ve employed them to do and if their qualifications are up-to-date on the back. Alternatively you can check the Gas Safe Register website.

For oil boilers, check that the engineer is Oftec registered – they will have undergone a thorough training and assessment program to government-recognised standards, much like Gas Safe, only with a focus on oil systems.

What does a boiler service involve?

There are several key checks an engineer will make when inspecting and servicing your boiler. They'll check:

  • For any signs of corrosion or leaking around the inside and outside of your boiler
  • All controls are working safely and effectively
  • Whether the gas pressure is too high or low
  • All internal parts are clean and safe
  • For any toxic emissions (such as carbon monoxide) being released into your home

If removing the cover isn’t possible, the engineer will conduct a Flue Gas Analysis test to check how much carbon monoxide is being pumped out of the device.

If you have a condensing boiler, the engineer will remove and clean the condense trap

Why do you need a boiler service? 

A faulty or poorly-maintained boiler could be the cause of a number of problems, and even put your safety at risk. *According to the Department of Health and Social Care, around 4,000 people each year go to A&E with carbon monoxide poisoning, with 200 people being hospitalised and around 50 people dying annually. This deadly gas is impossible to detect by scent, so you should have a carbon monoxide alarm located near any gas appliances and allow for regular servicing to help detect any leaks early on.

A regular service can also help with:

  • saving energy (and money on your bills) – by keeping your boiler running as efficiently as possible, an annual service means you can help save energy, and money.
  • Avoiding breakdowns – catching any potential issues and keeping your boiler in great condition means you’ll help avoid total breakdowns, which could end up leaving you and your household without heating or hot water until the problem can be fixed and incur unexpected repair bills.
  • Preventing full replacement of your boiler – by consistently keeping your boiler running smoothly, you’re more likely to delay the need to replace it completely, which comes at a high financial cost. Boilers that are not serviced regularly will be more prone to breakdowns which can, in some cases, result in the boiler needing to be replaced.

When to service your boiler

It’s generally recommended that you get your boiler serviced annually – this is the optimum amount of time to leave it so your engineer can catch any potential issues.

  • Have it serviced well before winter, this will ensure your boiler is working properly before the cold weather hits and it ramps up its activity.
  • Whilst you may not think about your central heating during the warmer summer months, it’s a great time as the engineers are less likely to be busy.
Setting the timer on a boiler

Are boiler service plans worth it?

Boiler service plans, also known as boiler cover, can help offer peace of mind in the case of any problems occurring with your boiler. In most cases, in return for a monthly fee, you’ll be assured that an engineer will be sent out to you to get your boiler back up and running.

Boiler with toolbox

Do I get a boiler service certificate afterwards?

Once your Gas Safe engineer is finished servicing your boiler, you can ask them to provide a summary of the service. It’s not a legal requirement but it is good practice.

You can usually expect it to include details on:

  • which parts of the boiler have been checked or tested
  • any problems that have arisen,
  • any advised works that have been recommended

If you are a landlord you will legally require a more formal summary, commonly known as a Gas Safety Record to prove you’ve had an inspection carried out. The Gas Safety Record is also commonly referred to as a Gas Safety Certificate or a CP12 and is a standardised form that engineers need to fill out for customers who are legally required to have a boiler inspection.

  • Homeowners – a Gas Safety Record is not a legal requirement, but you can ask for one for your own records or to prove to future buyers that you’ve kept your boiler in good condition.
  • Landlords – it’s a legal requirement to get the boiler inspected annually, along with all other gas installations and appliances owned by you in your properties (you don’t need to be concerned with appliances owned by your tenant but most engineers will give these a visual inspection and make a record of the inspection anyway). You’ll need a Gas Safety Record as proof of this, which you can provide for your tenant every 12 months.
  • Tenants – your landlord will need to provide you with a Gas Safety Record within 28 days of the boiler inspection.

*a department of Her Majesty's Government, responsible for government policy on health and adult social care matters in England.