A Guide to Boiler Servicing

02nd July 2022

A boiler service is a thorough assessment of your household’s boiler. It includes a series of checks and tests, and cleaning, to help the boiler operate correctly and safely. As a homeowner or landlord, getting your boiler serviced regularly is important and, in this guide, we’ll tell you everything you might need to know.

What’s included in a boiler service?

During an annual service, an engineer will thoroughly inspect and clean your boiler. Once the service is complete, you’ll receive a full report, including details about any faults or necessary repairs. Here’s what to expect from the boiler tests and checks.

Visual inspections

An engineer will visually inspect the boiler first to identify any obvious faults or issues, listed below, that could prevent it from working properly.

• Water leaks. 
• External and internal damage to the boiler, including the electrical components.
• Evidence of poor-quality installation.
• Combustible materials close to the boiler that could pose a hazard.
• Accessibility for repair and service.
• Signs of overheating or stress.

The engineer will also examine the boiler controls, making sure they’re fit for purpose.

Tests to check boiler efficiency

The engineer will turn on your boiler and let it run, allowing them to identify any operational faults. During the service, the engineer will also remove the boiler’s casing to check the individual components, such as the burner, the heat exchanger, and the spark sensor probe. They’ll also review the gas rate – the volume of gas used by the appliance. Using the manufacturer’s guide for reference, the engineer can tell if the gas rate is correct. If the rate is not correct, the engineer will look for the root of the problem. A flue gas analysis and a boiler tightness test will conclude the efficiency checks for your boiler.

Boiler and ventilation gas safety checks

Perhaps more importantly, the engineer will also test your boiler to make sure it is functioning safely. The boiler’s stability will be checked, in addition to the combustion and case seal. When inspecting the boiler’s individual components, the engineer will look for any localised faults that could pose a safety risk. If your boiler is older, the engineer might need to check its heating cylinder and dismantle the burner, fan and heat exchanger for a closer safety inspection. This usually isn’t necessary for modern boilers unless the flue gas analysis flags a major problem.

As for ventilation, the engineer will check any air vents, flues, or chimneys as part of the service. They’ll also carry out a flue flow tightness test and what’s known as a spillage test to check that nothing combustible will leak from your boiler.

System pressure checks

Your boiler’s ‘working pressure’ refers to the correct operating pressure for each individual component. While there is an in-built safety margin, it’s important to have the right pressure for your boiler and the wider heating system. As part of your boiler’s service, the engineer will analyse the pressure of your heating system across three different points; the boiler, the inlet burner, and the gas meter. If the working pressure is incorrect, the service will identify and potentially rectify the problem – leaving you with the correct pressure throughout your home.

Who should service your boiler?

When it comes to servicing gas boilers, only Gas Safe engineers authorised by the Gas Safe Registry, are permitted to carry out the task. In the case of an oil boiler, you’ll need a service by an OFTEC-registered engineer. You should contact a HETAS-registered engineer if you have a coal, wood-fired, or any other solid-fuel burning boiler. 

You will need to book an appointment for boiler servicing in advance. We recommend booking a service in summer instead of winter. Engineers tend to be busier in winter, so finding one when you need a service most could be difficult. Usually, you’ll find more availability in summer, and some companies will even offer discounts if you book during the warmer months. 

It will typically take a professional engineer under an hour to service your boiler. Make sure access to your boiler is possible, and there’s no clutter in the way. Any obstructions could delay the boiler servicing.

How much does a boiler service cost?

You can expect to pay around £85 to £100 for a full boiler service, although the price depends on the service provider and the circumstances of your boiler. For example, the service for an older boiler tends to be more expensive, often because replacement parts are harder to come by. Oil boiler services tend to be pricier too, but not by much. Always reach out for several quotes and compare your options. That way you’ll find the best possible price. 

As mentioned, the initial boiler service cost might not cover some faults and repairs. You could find yourself facing extra charges if the engineer encounters a problem. However, a good boiler cover package will come with servicing included, and this can help you avoid additional costs.

5 Reasons to Book An Annual Boiler Service

Unless you’re a landlord – in which case there are legal requirements for boiler servicing – you might wonder if a service is really necessary. Homeowners don’t have the same obligations, but that doesn’t mean you should pass on a boiler service. Read on to learn why you should book your annual boiler service today.

1. Carbon monoxide prevention

Carbon monoxide poisoning is one of the biggest safety risks posed by a faulty boiler. Between 1995 – 2019, over a quarter (26%) of deaths from unintentional carbon monoxide poisoning in the UK were caused by defective central heating boilers. While this number has reduced in recent years, largely due to the Gas Safety Record for landlords and householders, the risk is still present. A boiler service minimises the risk of carbon monoxide related incidents. You should also install a carbon monoxide alarm to identify any gas leaks.

2. General safety

There are several safety risks with a faulty boiler, besides carbon monoxide. This includes leaks of combustible products. Boiler servicing prevents potentially damaging leaks, keeping you safe and saving on the cost of repairs and replacements.

3. Identification of potential faults

An annual boiler service should identify areas that may need repair in your system. By identifying such faults, you can prevent a sudden, inconvenient breakdown. It’s worth organising your boiler service in the warmer months. This allows plenty of time for any repairs ahead of winter. Boiler servicing keeps you prepared and causes less disruption to your household.

4. Efficiency – extended lifespan and reduced bills

During a boiler service, an engineer will check whether your boiler operates efficiently and in line with the manufacturer’s standards. The engineer will make any necessary updates, leaving your boiler running in a more energy-efficient way. Not only will this prolong the boiler’s lifespan, but it can also save you money. An energy-efficient boiler uses fuel economically, potentially reducing your bills. Annual boiler servicing maximises the efficiency of a boiler, and in turn, it may reduce your expenses.

5. Manufacturer warranty validation

Most boiler manufacturers require an annual service to validate your boiler’s warranty. The service should be in line with the manufacturer’s standards. For instance, an engineer should conduct a Worcester boiler service in line with Worcester’s manufacturer standards. Your engineer may need to access the boiler’s operating manual to complete the servicing. These are often available online if you do not have the original hard copy.

Get a free annual boiler service with Hometree

Hometree’s boiler and home cover plans include an annual boiler service, saving you the hassle and cost of booking a one-off appointment. That’s not all; our plans cover the costs of boiler repairs should you encounter a fault. We’ll also help with any thermostats, programmers, valves or pumps that run into a problem. All parts and labour costs accounted for, we’ve got you covered. With a 24/7 helpline and nationwide coverage, our experts are here to help all year round, whenever you need us. Protect your home with Hometree boiler and home cover today.