Common problems guide

The most common Chaffoteaux Britony II 50FF problems

The faults most likely to send a Chaffoteaux Britony II 50FF into lockout — with plain-English causes, what to check first, estimated repair costs and whether you need a Gas Safe engineer.

This model is discontinued. Parts can be harder to source and expensive. If repair costs are mounting, a new A-rated boiler may be the smarter choice.
22 documented codes
6 most common
1 DIY-safe checks
5 engineer needed

The 6 most common faults

01
8.12 High DIY-safe

Your boiler has stopped working because the water pressure inside the heating system has dropped too low.

What to try first

Locate the filling loop, which is a silver braided hose with one or two valves connecting your boiler to the mains water supply.Open the valve(s) slowly to allow water into the system while watching the pressure gauge on the front of your boiler.Stop filling when the needle reaches the green zone, typically between 1 and 1.5 bar, then tightly close the valve(s).

Est. cost
£80-150
Parts
Filling loop, Pressure relief valve, Pressure sensor
Full guide for 8.12
02
8.4.2 High Engineer

Your boiler is struggling to keep the flame lit while you are trying to use hot water, causing it to cut out during use.

Est. cost
£150-250
Parts
Flow sensor, Diverter valve diaphragm, PCB
Full guide for 8.4.2
03
8.5 High Engineer

Your boiler is currently unable to ignite its main flame, meaning it cannot produce any hot water or heating for your home.

Est. cost
£120-250
Parts
Ignition electrode, Gas valve, Printed Circuit Board (PCB)
Full guide for 8.5
04
8.1 High Engineer

Your boiler is failing to ignite its flame, which means it cannot produce any hot water or heating for your home.

Est. cost
£120-250
Parts
Ignition electrode, Ignition lead, Gas valve
Full guide for 8.1
05
8.2 High Engineer

Your boiler is struggling to keep its internal ignition flame lit, which prevents the main burner from starting and means you will currently have no hot water or heating.

Est. cost
£120-250
Parts
Pilot injector, Spark electrode, Ignition lead
Full guide for 8.2
06
8.3 High Engineer

Your boiler is failing to keep its small starter flame lit, which prevents the main system from firing up to provide you with heating or hot water.

Est. cost
£120-250
Parts
Thermocouple, Pilot assembly, Ignition electrode
Full guide for 8.3
Parts most often replaced

on the Chaffoteaux Britony II 50FF

Filling loopPressure relief valvePressure sensorFlow sensorDiverter valve diaphragmPCB

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
See the full 22-code list for the Chaffoteaux Britony II 50FF

Related guides

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