Medium
05 on Vokera Syntesi 25E / 29E

Your boiler is struggling to talk to your room thermostat or remote control unit, which is preventing it from knowing when to turn the heating on.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Fault code 05 appears if the appliance is connected to the optional remote control (RC05) and there is a communication problem.

From this model's manual
Verified against the Vokera Syntesi 25e 29e installation & service manual, page 34.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Locate the remote control unit and check that it has fresh batteries.Turn the boiler off at the mains power switch for 60 seconds to reset the connection.Check the wiring connections behind your thermostat to ensure no wires have come loose.

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