BoilerFaultCodesYour boiler is having trouble directing hot water between your taps and radiators due to a mechanical issue with a internal valve.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Diverter valve by Wilo
What causes this fault?
This fault occurs when the internal moving parts of the diverter valve become stuck or the motor that drives them fails to reach the correct position. This is often caused by a buildup of debris or sludge from the heating system water creating friction, which prevents the valve from switching between your heating and hot water.
This fault is more frequent in autumn when the heating is turned on for the first time after summer, as the valve may have seized during the long period of inactivity.
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 →Protect yourself from future repair bills
A boiler cover plan would cover faults like 65:2 — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
Affiliate links — we may earn a commission at no extra cost to you.