Burner Lockout
The oil burner has gone to lockout — the red lockout light on the burner control box is illuminated. The most common Grant oil boiler fault. Can be caused by no fuel, blocked fuel filter, or air in the fuel line.
In cold weather, the oil fuel itself can become viscous and restrict flow. Check the oil tank and ensure it is not nearly empty.
Step-by-Step Fix Guide
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Step 1
Check the oil tank level — the most common cause is running out of oil
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Step 2
Check the oil supply valve is fully open
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Step 3
Check the oil filter for blockage
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Step 4
If oil supply is present, press the red reset button on the burner control box ONCE
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Step 5
If the burner locks out again, do NOT keep pressing reset — call an OFTEC registered engineer
Work on gas appliances must be carried out by a Gas Safe registered engineer. The steps above cover safe checks a homeowner can perform - any internal component replacement requires a qualified professional. If in doubt, always call an engineer.