0E34 Medium

Alpha 0E34 Fault Code

The Alpha 0E34 fault code means: your boiler is struggling because the electricity supply it is receiving is weaker than it should be.. It appears on 2 Alpha models in our database.

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: Low powers supply voltage.

What causes the Alpha 0E34 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 £100-250 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Avoid the next call-out bill

A cover plan would handle faults like 0E34: no call-out fees, no surprise bills.

Approved partner
Domestic Appliance Guard
Unlimited call-outs, 24/7 helpline, no price-hike promise
Get a quote →

Affiliate links. We may earn a commission at no extra cost to you.

Alpha models that show the 0E34 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Alpha 0E34 fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026