BoilerFaultCodesThe 6 most common faults
01
A02.06 High DIY-safe
Your boiler has detected that the water pressure inside your heating system has dropped too low, which prevents it from working correctly.
What to try first
Locate the external filling loop, which is usually a flexible silver hose connected to two valves under the boiler.Open the valves slowly to allow mains water into the system until the pressure gauge on the boiler front reads between 1.0 and 1.5 bar.Close both valves tightly to prevent over-pressurisation.
02
E00.00 High Engineer
Your boiler has detected a safety issue and has shut itself down completely to prevent damage or danger.
Full guide for E00.0003
A00.42 High Engineer
Your boiler has stopped working because it cannot detect the water pressure in the system, usually due to a loose wire or a faulty sensor connection.
Full guide for A00.4204
A01.23 High Engineer
Your boiler has detected that the fuel and air mixture used to heat your home is not burning correctly, so it has safely shut itself down to prevent unsafe operation.
Full guide for A01.2305
A02.36 High Engineer
Your boiler has lost communication with an internal control module, meaning it cannot safely operate until the connection is restored.
Full guide for A02.3606
A02.37 High Engineer
Your boiler has lost communication with an internal accessory or control component, which is preventing it from operating correctly.
Full guide for A02.37on the Remeha Quinta Ace 30
Pressure sensorFilling loopPressure relief valveIgnition electrodeFlame sensorGas valve
Based on parts cited in our fault code database. Your engineer will confirm what's actually needed after diagnosis.
Call a Gas Safe engineer if…
- You can smell gas or see signs of a leak
- The Remeha 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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