An oil boiler service is essential for maintaining the safety, efficiency and longevity of your heating system. By following a thorough service routine each year, you can prevent breakdowns, lower fuel bills and ensure consistent warmth throughout the colder months. Here’s a detailed look at every stage of a professional oil boiler service.
Oil boiler service: step-by-step overview
Initial preparation
The engineer arrives equipped with all necessary tools and safety equipment. First, they switch off the boiler at the control panel and isolate the oil supply valve. Protective covers or trays are laid down to catch any drips, and the surrounding area is cleared to provide safe, unobstructed access. This preparation helps prevent accidental spills and ensures the engineer can work efficiently.
Visual inspection
A thorough visual check follows, covering the boiler casing, flue, burner and pipework. The engineer looks for signs of corrosion, oil leaks or cracked seals. They’ll verify that the flue outlet is free from obstructions like bird nests or debris and confirm that air vents and ventilation grills around the boiler aren’t blocked. Any visible damage or wear is noted for further investigation or immediate repair.
Combustion analysis
Next, a flue gas analyser is connected to the flue pipe to measure key performance indicators: carbon monoxide levels, oxygen content, flue gas temperature and combustion efficiency. These readings indicate whether fuel is burning cleanly and safely. If CO levels exceed safe limits, the engineer will adjust the burner settings or recommend component replacement to restore optimal combustion.
Cleaning components
Over time, soot and carbon deposits build up on the heat exchanger, burner nozzles and electrodes, reducing efficiency. The engineer removes and brushes or solvent-cleans these parts, often using specialised descaling tools. Cleaning restores proper heat transfer, improves ignition reliability and can boost your boiler’s fuel economy by several percentage points.
Safety checks and adjustments
Safety devices are critical for preventing accidents. The pressure relief valve is tested to ensure it opens at the correct pressure. The low-water cut-off and pressure gauges are checked for accuracy, and the flame safeguard controls are tested to verify they shut down the burner in unsafe conditions. Any worn gaskets or seals are replaced to eliminate future leaks, and wiring connections are tightened.
Final testing and report
With internal components cleaned and safety devices calibrated, the engineer restarts the boiler and observes several minutes of operation. They confirm steady flame quality, correct pressure readings and normal pump operation. All test results are logged in a comprehensive service report, which includes notes on any recommendations—such as parts due for replacement—and advice on how to maintain peak performance between annual services.
Looking for year-round reliability from your oil boiler in Birmingham, Stourbridge, Dudley and Wolverhampton?
Bog Standard Plumbing and Heating offers expert oil boiler servicing, detailed inspections and professional advice to keep your home warm and safe. Call us on 0330 113 2248 or fill out our contact form to book your service today.
