Gas Boiler Servicing / Repair in Sunbury-on-Thames, Surrey (122)

Search the Gas Safe Register to find qualified gas boiler servicing engineers in your local area.

You can also find reputable boiler engineers working in Sunbury-on-thames by asking for recommendations and reading online customer reviews.

Search Checkatrade to find checked and verified tradespeople working near you and covering your postcode. We only approve boiler servicing engineers who pass our checks and meet our standards.

Before you hire someone to service your gas boiler, it’s important to ask the right questions. This can help you find someone you consider qualified and a good fit for the job. Here are some useful things to ask:

• Are you Gas Safe registered?
  • It’s a legal requirement for anyone working on gas appliances. Always ask to see their Gas Safe ID.
• What qualifications do you have?
  • Many engineers will also hold an NVQ Level 3 or equivalent in gas installation and maintenance.
• Are you a member of any Competent Person schemes?
  • You can check this using the schemes’ online registers.
• Do you have public liability insurance?
  • This protects you and the engineer if anything goes wrong.
• What does your boiler service include?
  • Get clear on what checks, tests and reports you’ll receive.
• Do you offer written quotes?
  • It’s good practice to get a breakdown of costs before work begins.
• Do you provide follow-up support or guarantees?
  • Useful to know if something goes wrong after the service.

It’s also a good idea to:

• Ask how long the service will take (usually around one hour)
• Confirm if parts or repairs are extra
• Check how soon they can carry out the work

Gas boiler engineers need the right training and certifications to legally and safely service your boiler. Here's what to look for:

• Gas Safe registration
  • This is non-negotiable. Any engineer working on a gas appliance must be on the Gas Safe Register. You can check this online or ask to see their ID.
• NVQ Level 3 (or equivalent)
  • Many engineers will hold an NVQ diploma in gas installation and maintenance. This qualification proves they’ve been trained in both theory and hands-on experience.
• Appliance-specific training
  • Some engineers may have manufacturer-approved training, especially for major boiler brands like Worcester Bosch, Vaillant or Ideal.

Hiring someone without the right qualifications could void your boiler warranty, and poor work can lead to safety risks like gas leaks or carbon monoxide.

Alongside the relevant qualifications and experience, a gas boiler engineer must also have public liability insurance. This insurance offers protection for homeowners and boiler engineers if any damage is caused during the boiler service or repair work.

Gas boilers should be serviced every 12 months. An annual service will make sure your boiler continues to perform at its best.

It takes approximately one hour for a gas engineer to service a boiler. Several checks and tests will be carried out during the service to make sure everything is working correctly and no repairs are needed.

All boilers, even new installations, need to be serviced annually. Failing to service a boiler every year can void your warranty and also lead to problems and damage being missed.

A yearly check-up is important for:

• Safety - A yearly service helps identify gas leaks, faulty components, and potential carbon monoxide risks
• Saving on energy bills - A well-maintained boiler uses less gas and electricity
• Catching problems early - Small faults can become big breakdowns if ignored
• Keeping your warranty valid - Most manufacturers require annual servicing to uphold the warranty

The best time to book a service is during the warmer months - between spring and early autumn - when engineers are less busy and you’re not relying on your central heating every day.

A thorough boiler service should include a range of checks and maintenance steps to ensure your gas boiler is safe and running efficiently. Here’s a breakdown of what’s typically included:

• Visual inspection – Checking the boiler for any signs of wear, corrosion, or leaks.
• Flue inspection – Ensuring the flue is safely fitted and removing exhaust gases properly.
• Control checks – Verifying all operational and safety controls are working.
• Gas pressure check – Ensuring the boiler is operating at the correct pressure.
• Component cleaning (if needed) – Cleaning key parts such as the burner, heat exchanger, and fan if necessary.
• Ignition system test – Confirming the boiler ignites and shuts down correctly.
• Boiler casing check – Making sure all external seals are secure and the unit is properly sealed.
• Boiler service report – Completing the documentation required for warranties or legal purposes.

Gas boilers are prone to several common issues. To avoid a full boiler replacement, it is important to know what signs to look out for and to get the problem fixed as soon as possible.

Signs of a faulty gas boiler include:

• Error codes displayed on the control panel
• Leaking water
• Unstable pressure
• Banging sounds
• Heating and hot water issues
• Gas leaks

You will need to hire an emergency boiler repair engineer if your boiler is experiencing any of the following:

• Gas leaks
• Faulty carbon monoxide detector
• Fast-flowing water leak
• No heating or hot water
• Full system shutdown

Contact an emergency boiler repairs service covering Sunbury-on-thames and switch off the boiler while you wait for help to arrive.

Emergency call-out charges can be higher - especially at weekends or during Bank Holidays - but ignoring serious gas boiler faults can be dangerous.

Hire a Checkatrade gas boiler engineer to get your heating and hot water up and running again.

In the meantime, you can:

• Check the basics – Confirm the thermostat, power supply, and pressure levels. Sometimes, a simple system reset or pressure top-up can solve the problem.
• Turn off the boiler – If you suspect a gas leak or can smell gas, shut down the boiler immediately and don’t attempt to relight it.
• Ventilate the area – Open windows and doors if you suspect a leak.
• Call the National Gas Emergency Service on 0800 111 999 if there’s a gas leak.