BoilerFaultCodesDaikin UA-65 Fault Code
Also written as UA65 — same fault.
The Daikin UA-65 fault code means: your boiler's main control board is currently unable to communicate with its internal memory chip and needs a software or hardware synchronisation.. It appears on 1 Daikin model in our database.
Technical description: Printed circuit board (PCB) requires a boiler chip card (BCC) update
What causes the Daikin UA-65 fault?
This fault occurs when the boiler's main control board loses its connection to the memory chip that holds the unit's specific configuration settings. It is often caused by a temporary data glitch, a loose connection on the circuit board, or the memory chip itself becoming faulty and unable to send instructions to the boiler.
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 →Daikin models that show the UA-65 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Daikin UA-65 fault code information on this page is sourced and cross-checked against the official Daikin service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026