Oil boiler not firing up: safe checks before calling

If an oil boiler will not fire, the cause may be as simple as a control setting or as technical as an oil supply, ignition or burner fault. Work through only the checks that do not require removing covers or disturbing fuel components.

Safe checks at home

1. Confirm the boiler has electrical power and that no local switch or fused spur has been turned off.
2. Check the programmer, room thermostat and cylinder thermostat are calling for heat.
3. Look at the oil tank level. A gauge can be inaccurate, so consider whether the tank may genuinely be empty.
4. Check whether the boiler displays a fault code or burner lockout light.
5. If appropriate, check that the system pressure is within the range stated by the boiler manufacturer.

Should I press reset?

You may try the burner reset button once. If the boiler does not start normally or locks out again, stop. Repeated resetting can introduce more unburned oil and may make the eventual ignition unsafe.

Common causes an engineer may find

Typical causes include an empty tank, air in the oil line, blocked filter or nozzle, failed ignition components, photocell problems, pump faults, faulty controls, frozen condensate on a condensing appliance or incorrect combustion.

Switch the boiler off and seek prompt help if there is smoke, soot, an oil or fume smell, oil leakage, unusual ignition noise or signs of overheating.

Local oil boiler fault finding

Gloucester Oil Burner Services diagnoses oil boilers that will not fire across Gloucester and nearby areas. Please include the boiler make, any fault code, what happens when it tries to start and your postcode.

Book an oil boiler repair | Resetting guidance | Annual servicing

Call or WhatsApp 07725 972140.

No hot water from an oil boiler quick checks

If your oil boiler is running but you have no hot water, the fault can be simple, but it can also point to a burner, controls, pump or hot water cylinder problem. This guide is for homeowners in Gloucester and nearby Gloucestershire areas who want to make a few safe checks before booking a repair.

Quick checks before calling an engineer

1. Check the programmer or timer. Make sure hot water is switched on and that the clock has not reset after a power cut.

2. Check the cylinder thermostat. If you have a hot water cylinder, the thermostat may be turned down or not calling correctly. Around 60C is common for stored hot water.

3. Check the oil level. If the tank is low or has run out, the boiler may lock out and need proper bleeding and recommissioning.

4. Look for burner lockout. If the red lockout light is on, try one reset only. If it locks out again, stop resetting it and call an oil boiler engineer. Repeated resets can make the fault worse.

5. Check whether the heating works. If the radiators get hot but the hot water does not, the fault may be with a motorised valve, pump, thermostat, programmer or hot water cylinder controls.

Common causes of no hot water

No hot water from an oil boiler can be caused by a faulty programmer, failed thermostat, stuck motorised valve, worn pump, airlock, blocked filter, dirty nozzle, photocell fault, poor combustion or burner lockout. Older systems can also suffer from wiring centre faults or cylinder coil issues.

When to call for help

Call an engineer if the burner locks out again after one reset, the boiler smells of oil or fumes, there is soot around the appliance, the boiler is noisy, or the hot water keeps cutting out. Do not remove the burner cover or adjust oil burner settings yourself.

Gloucester Oil Burner Services can help with oil boiler fault finding, oil boiler repairs and annual oil boiler servicing across Gloucester, Tewkesbury, Stroud, Cheltenham, Forest of Dean and nearby areas.

Useful pages on this website

Oil boiler repairs
Oil boiler service Gloucester
Oil burner service and repair Gloucester

Need help with no hot water from an oil boiler. Call or WhatsApp Gloucester Oil Burner Services on 07725 972140.