How a domestic oil heating system works: tank, supply, fire valve, burner and flue.
Many rural UK homes off the gas grid heat with oil (kerosene). The system mirrors a wet central-heating system but with an oil boiler.
Storage. Oil is kept in a tank, sited to fire-separation and environmental rules. An integrally bunded tank includes secondary containment around the primary store. Confirm whether containment is required and verify the tank’s design, effective capacity and condition; a tank with two walls may still not be a suitable bund.
Supply. Oil flows from the tank through a filter and a fire valve to the burner. The fire valve is a remote, heat-sensing valve that shuts off the oil if there is a fire/overheat at the appliance.
Burner. Most domestic boilers use a pressure-jet burner that atomises the oil for combustion; some use a vaporising burner.
Flue & combustion. An oil boiler needs its specified flue and combustion-air supply, together with correct commissioning. A room-sealed boiler takes its air through an outside connection; an open-flued one relies on the air provision for its installation space. Always follow the appliance instructions and the current standards.
Burner, filter and lockout
- A pressure-jet nozzle produces the specified oil spray. Match its capacity, angle and pattern to the appliance, and set the pump pressure as instructed: the delivered rate depends on pressure and fuel properties as well as the nozzle rating.
- Particle filtration protects fine pump and nozzle passages. Some nozzles also have a small built-in filter, but this does not replace the specified filters in the supply line. A filter may not remove water: investigate contamination and use the appropriate separation or treatment. Restriction can cause poor firing or lockout, but those symptoms have other causes too. A good tank level or a full filter bowl does not confirm adequate fuel delivery.
- A lockout records a safety shutdown. Read the model’s fault indication and investigate the cause before further reset attempts; failed ignition and lost flame are examples, not the only possible faults.
- Restricted combustion air can cause incomplete burning, soot and carbon monoxide. Fuel delivery, nozzle condition and burner settings also need attention; a clear air opening does not mean combustion is safe.
- Domestic tank-fed kerosene heating normally uses bulk deliveries. Include tank siting, safe filling, access and replenishment in the design, so the household can maintain its supply throughout use.