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It is recommended that the gas boiler in your commercial or residential property be serviced once every twelve months. The service must be carried out by a Gas Safe engineer who is qualified to work on the gas boiler.
This recommendation applies when the radiators heat up and the hot water flows. A service checks parts of the boiler that you cannot assess through everyday use.
The 12-month cycle must start from the date of your last service. If you have a new boiler, check its installation date and the manufacturer’s service requirements.
What Does “Once a Year” Actually Mean?
It means keeping about 12 months between services. Booking one appointment in each calendar year does not always achieve that.
Suppose your boiler was serviced in February 2025. The next service must be in February 2026. If you leave it till November, then it creates a gap of 21 months.
Always set a reminder a few weeks before the due date. This gives you enough time to book. You can also book recurring boiler service every year if your engineer provides that service.
You should also consider your manufacturer instructions if they provide the particular intervals. Follow any advice your engineer gives about further checks after a fault or repair.
HSE strongly advises annual service must be carried out by Gas Safe engineers.
Why Service a Boiler That Seems Fine?
Most people judge their boiler by two things. Does the heating come on? Is there enough hot water?
These checks tell you that your boiler is working fine. They don’t show you what is happening inside your boiler.
When you book boiler service, the engineer follows a method that fits your boiler model. They check the boiler operation and complete the required maintenance. If any problem is found during the visit, they must explain it to you before doing any repair work.
For instance, a small leak deserves attention even if the boiler still heats the house. Leaving it unresolved gives it time to cause further damage.
Servicing also has limits. It does guarantee that every part of your boiler will work fine till the next visit. If a fault appears afterwards, it still needs investigating.
There is no fixed saving on energy bills either. The result depends on the boiler’s condition and any problems corrected.
When Does a New Boiler Need Its First Service?
A new boiler usually needs service after 12 months. You can find the exact time frame in your paperwork.
If you got a new boiler installation in October, the service must be done in next year’s October. It is always advisable to book in advance to ensure the availability.
A long warranty doesn’t mean that the boiler doesn’t need annual service.
Worcester Bosch, for example, requires annual servicing to keep its guarantee valid. Its terms also state that the guarantee does not include the annual service itself.
Other brands have their own conditions. Read the terms that come with your boiler, including any needs, for service records.
Keep the installation papers and service history in the place. An invoice only shows about the payment. You should also have the record of the work done.
If you use another engineer next year, those papers give a helpful history.
Is There a Best Time to Book a Boiler Service?
Summer works best because the radiators are used less. It also gives you enough time to fix any issue found during the service before the winter comes.
Baxi suggests getting the heating system ready before winter, because during winter their support teams get very busy.
However, if your service comes in winter, don’t postpone it. A boiler installed or serviced in January should not wait till August just to move the appointment to summer. If you want a different month, discuss this before moving to another month.
Your schedule also matters. Someone will need to provide access to the property and the boiler.
If the boiler is inside a cupboard, make sure to move any items stored there first. Tell the company if access is difficult, especially if the boiler is in a loft.
What Should You Do About an Overdue Service?
If your service is late, discuss it with your gas engineer before booking an appointment. Tell him how long it’s been since the last service.
Don’t wait for the next service cycle if you get it late. Nor assume that the boiler is safe just because it is working.
If annual service is missed, it does not automatically prove that something is wrong. It means the scheduled assessment and maintenance have not taken place.
The engineer will check the boiler’s current condition. Tells you about any leaks, unusual noises, fault codes, or recent repairs when booking.
If your warranty is still valid, contact the manufacturer and tell them about the missed service. The effect on cover depends on its terms. A late appointment does not automatically settle that question.
This is also worth checking when buying a house. The installation certificate shows when the boiler was fitted. It does not prove that it has been serviced since.
Ask the seller for the maintenance records. If they are unavailable, arrange a service and explain that the history is unknown.
What Happens During an Annual Boiler Service?
The work always followed the instructions given by the manufacturer and boiler model.
It generally includes an inspection, operational checks, and the required testing and maintenance. Cleaning depends on the appliance and its service procedure.
You do not have to know the names of each part. The important thing is to understand what the engineer has found.
Before the visit finishes, you should know if the service is finished and if more work is required. Ask for an explanation of any recommendation that you do not understand.
It helps to bring up any problems right at the beginning. A boiler might behave normally during the appointment but lose hot water on other days.
Describe what happens and when. If any fault code appears, note it down. Don’t repeatedly reset your boiler because it will make it difficult to explain the issue.
Any repair work is not included in annual service. If you found any fault mentioned during booking a company, they can schedule their appointment.
Is a Boiler Service the Same as a Landlord Gas Safety Check?
No. They cover different responsibilities.
A landlord must arrange annual gas safety checks for relevant appliances and flues supplied for tenants. They must also maintain the gas equipment they provide.
Servicing addresses the boiler’s maintenance needs. The landlord check covers the required safety checks and records.
HSE says neither job should automatically be treated as a substitute for the other. A service does not necessarily include every required landlord check. A safety check alone does not necessarily provide enough maintenance.
Both jobs can be talked about when setting up the appointment. Make sure to find out what is covered and which documents will be given. Residents need to let the landlord know about problems as soon as they occur. A heating problem in December should not be left until a scheduled visit in March.
Our landlord gas safety certificate service explains how to arrange the required check.
When Does a Boiler Need Attention Sooner?
The annual schedule is for routine maintenance. A current fault needs a separate decision.
Contact an engineer if the boiler:
- Repeatedly switches off.
- Loses pressure regularly.
- Leaks water.
- Fails to provide reliable heating or hot water.
- Makes a new or persistent unusual noise.
Explain the symptoms when booking. A repair visit provides time to investigate the fault. Asking for a routine service may leave the company unprepared for the repair work required.
Do not remove the casing. Neither attempt to gas repair yourself. If you suspect a gas leak, call the National Gas Emergency Service on 0800 111 999 immediately from a safe place. Stop using any appliance you believe is unsafe.
Frequently Asked Questions
Does a combi boiler need servicing every year?
Yes. A gas combi boiler needs annual servicing according to its manufacturer’s instructions. Supplying both heating and hot water does not change that requirement.
Does a boiler repair count as a service?
Only if the required service work was completed too. Replacing a faulty part does not automatically amount to a full service. The paperwork should show what the engineer did.
Do older boilers need servicing twice a year?
Age alone does not set a six-month service interval. Continue annual servicing unless the manufacturer or engineer advises otherwise. Recurring faults need investigation when they appear.
Can I use a different engineer next year?
Yes. The engineer must be Gas Safe registered and qualified for your appliance. Provide the previous service records and mention any repairs. Check your warranty for additional conditions.
Arrange Your Next Boiler Service
If your annual service is due, contact Unique Gas and Heating Solutions to arrange an appointment.
Our boiler servicing service is available to homeowners and landlords. Tell us your boiler’s make, its last service date, and whether anything has changed since the previous visit.
