Common problems guide

The most common Vokera Unica problems

The faults most likely to send a Vokera Unica into lockout — with plain-English causes, what to check first, estimated repair costs and whether you need a Gas Safe engineer.

19 documented codes
6 most common
0 DIY-safe checks
6 engineer needed

The 6 most common faults

03
A01 Engineer

Ignition failure - Reset; ensure gas supply is turned on, if problem persists, call engineer.

Full guide for A01
04
A02 Engineer

Limit thermostat fault - Reset; ensure suffi cient water pressure, if problem persists, call engineer

Full guide for A02
06
A04 Engineer

Insuffi cient system water pressure - Reset; ensure suffi cient water pressure, if problem persists, call engineer

Full guide for A04

Call a Gas Safe engineer if…

  • You can smell gas or see signs of a leak
  • The Vokera shows an Emergency or High severity code
  • The boiler keeps locking out after repeated resets
  • You've tried the DIY checks and the fault hasn't cleared
  • There's visible water leaking from the boiler
  • The flame is yellow or orange instead of blue
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See the full 19-code list for the Vokera Unica

Related guides

Boiler losing pressure → No hot water → When to replace → Symptom checker →