Your boiler has detected a lockout fault and has shut down to protect itself, meaning your heating and hot water will not work until it is reset.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Led alarm (red)
What causes this fault?
This fault occurs when the boiler fails to detect a flame after several ignition attempts, causing the system to shut down for safety. The most common reasons are a lack of gas supply to the unit, a blocked burner, or a faulty sensor that cannot confirm the flame is lit. It can also be caused by worn-out electrical components that are responsible for creating the initial spark.
DIY fix possible
Locate the mode selector switch on the front panelTurn the switch to the 'OFF/RESET' positionWait for 5-10 secondsTurn the switch back to either 'Hot Water Only' or 'Heating and Hot Water'
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like LD1 — no call-out fees, no surprises.
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Vokera Option is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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