BoilerFaultCodes 0E34 Medium Lockout
Your boiler's hot water sensor is reporting an unusual temperature reading, which means the system cannot safely heat your water.
Book a service
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: DHW sensor out of range (measures a temperature outside normal working range.)
What causes this fault?
This fault occurs when the sensor responsible for monitoring your hot water temperature sends an impossible reading to the boiler's internal computer. It is usually caused by the sensor failing internally due to age or a loose connection in the wiring that prevents the signal from reaching the control board.
Typical repair cost £90-160 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 0E34 — no call-out fees, no surprises.
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