Who should service the oil boiler and tank?

Oil boilers are common across rural Ayrshire, from farmhouses in the Doon valley to cottages along the Carrick shore where there is no mains gas. They are reliable when looked after, but the burner, nozzle and flue need regular attention to stay safe and efficient.

Gas Safe registration does not cover oil. The scheme for oil-fired boilers, tanks and pipework is run by OFTEC, which registers technicians for different kinds of work.

How often should an oil boiler be serviced?

At least once a year, or as the maker's instructions say. OFTEC's home guide to liquid fuel appliances says liquid fuel appliances should be serviced at least annually or in line with the manufacturer's instructions, that parts such as nozzles, flexible hoses and wicks should generally be replaced at each service, and that an annual service should include checking the fuel storage tank and its pipework.

The same guide says an appliance should never be placed where a ladder is needed to maintain it, and recommends an audible carbon monoxide alarm as a precaution.

What does the technician check?

OFTEC's guide to liquid fuel heating says the tank should be inspected every year as part of the heating service, and that the technician will tell you when it is time to replace it. The registered technician completes a CD/11 service and commissioning report for your records.

Keep those CD/11 forms with the house papers. They show what was found, and they help when you sell, claim on insurance or need a warranty repair.

How do we check someone is registered?

Use OFTEC's registered technician search. You can find a technician by the type of work, such as servicing an oil-fired boiler or inspecting an oil storage tank, or check whether a named business is currently registered. OFTEC notes that the search only lists businesses and technicians registered now, not those registered in the past.

OFTEC's home guide adds that it gives each registered technician a photo ID card and checks that registered businesses hold public liability insurance. Ask to see the card when the technician arrives.

Do the same rules apply in Scotland as in England?

Not quite. OFTEC's home guide says registered technicians in England and Wales can self-certify new installations, and that a similar optional scheme is available in Scotland. In Scotland, a new tank or boiler must still meet the building regulations, and OFTEC notes you may need to apply for a building warrant. The tank siting rules are covered in how close an oil tank can be to the house.

Why does a carbon monoxide alarm matter here?

Any boiler that burns fuel can produce carbon monoxide if it is faulty or its flue is blocked. Scottish Fire and Rescue Service says a carbon monoxide detector should be fitted in any room with a carbon-fuelled appliance, and that this is now a legal requirement in homes in Scotland. Siting is covered in do we need a carbon monoxide alarm.

Between services, you can do your own visual checks of the tank. OFTEC's tank-check advice lists what to look for, and how long a plastic oil tank lasts covers ageing tanks.

What to look at first

1. The date of the last service and the CD/11 form from it.
2. The OFTEC registration of the business you plan to book.
3. A working carbon monoxide alarm in the boiler room.
4. Clear, safe access to the boiler and the tank.
5. The tank itself: cracks, bulges, rust or oil stains.

Yours to do, and theirs

You can

• Book the service each year and keep every CD/11 report.
• Check the technician's registration on OFTEC's search and ask to see the photo ID card.
• Test the carbon monoxide alarm and keep the area round the boiler and tank clear.

Leave to them

• Servicing the burner, nozzle, flue and fuel line is for an OFTEC-registered technician.
• Inspecting the tank and advising on replacement is for an OFTEC-registered technician.

In short

Book an OFTEC-registered technician to service the oil boiler at least once a year, and make sure the visit includes the tank and its pipework. Check the registration online, keep the CD/11 reports, and keep a working carbon monoxide alarm in the room.

Also asked about this

Can a Gas Safe engineer service an oil boiler?

Gas Safe registration covers gas and LPG work. For oil, look for an OFTEC-registered technician.

What is a CD/11 form?

It is OFTEC's service and commissioning report, which the registered technician completes at a service for your records.

Our boiler is new. Does it still need a service in year one?

OFTEC's guide says at least annually or as the maker's instructions say, so year one is included.

Is a range cooker on oil serviced the same way?

OFTEC's home guide covers oil-fired cookers alongside boilers and says liquid fuel appliances should be serviced at least annually.

Sources, checked 5 November 2026

1. OFTEC — Home guide to domestic liquid fuel-fired heating and cooking appliances (PUB 31)
2. OFTEC — Your home guide to liquid fuel heating
3. OFTEC — Registered technician search
4. OFTEC — Advice on oil tank checks for households as fifth miss annual boiler service
5. Scottish Fire and Rescue Service — Heating and gas