BoilerFaultCodesThe 6 most common faults
01
Pilot will not light High Engineer
Your boiler is failing to ignite because it cannot receive or properly process the gas needed to create a flame.
Full guide for Pilot will not light02
Complaints of noise High Engineer
Your boiler is making unusual noises because of internal blockages or issues with how it regulates heat or water flow, which can put unnecessary strain on the system.
Full guide for Complaints of noise03
MAIN BURNER DOES NOT LIGHT High Engineer
Your boiler is failing to ignite the flame needed to heat your water or home, which means the system has stopped working entirely.
Full guide for MAIN BURNER DOES NOT LIGHT04
WATER TEMPERATURE LOW High Engineer
Your boiler is struggling to heat the water to the right temperature because the water is flowing through the system too quickly or the gas supply isn't strong enough.
Full guide for WATER TEMPERATURE LOW05
BURNER STAYS ON High Engineer
Your boiler is failing to switch off even when it should, which means it will continue to run constantly and may overheat.
Full guide for BURNER STAYS ON06
INSUFFICIENT WATER FLOW High Engineer
Your boiler is struggling to detect enough water flowing through it to safely start your hot water.
Full guide for INSUFFICIENT WATER FLOWon the Chaffoteaux Corvec 28 OF BF
Fusible linkGas valvePilot assemblyHeat exchangerCentral heating pumpWater flow filter
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 Chaffoteaux 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