Baxi Bahama 100 Fault codes & diagnostics

6 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Combi Natural Gas 29 kW 2000-2006 Discontinued

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Severity at a glance

Each cell = one fault code. Hover to identify.
1 Emergency 3 High 2 Low
Just want the most common Baxi Bahama 100 faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes

All 6 documented codes

Tap any card for details

Flame Failure

Your boiler has stopped working because it couldn't light the flame or keep it burning, so it has purposefully shut itself down for safety.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Printed Circuit Board (PCB)
  • Flame rectification probe
Full explanation for Flame Failure
Green Light

Your boiler is working normally and simply letting you know that it is powered on and ready to provide heating or hot water.

Low DIY-safe

What to check first

  1. No action required as this is the standard operating status indicator.
Full explanation for Green Light
Pressure Gauge 3 or greater

Your boiler has become dangerously over-pressurised, meaning there is too much water inside the system.

Emergency Engineer only £120-200

Parts commonly replaced

  • Pressure Relief Valve
  • Filling Loop
Full explanation for Pressure Gauge 3 or greater
Pressure Gauge below 1

Your boiler has lost the water pressure it needs to circulate heat, which means it will stop working until the system is topped up.

High DIY-safe £80-150

What to check first

  1. Locate the filling loop, which is a silver braided hose connecting two pipes underneath the boiler.
  2. Open the valves at both ends of the hose to let water into the system while watching the pressure gauge.
  3. Close both valves firmly once the needle sits between 1 and 1.5 bar.

Parts commonly replaced

  • Filling loop
  • Pressure relief valve
  • Expansion vessel
Full explanation for Pressure Gauge below 1
Red Light

Your boiler has stopped working because it has detected an internal overheating issue or a failure to light the burner as a safety precaution.

High Engineer only £120-250

Parts commonly replaced

  • Overheat Thermostat
  • Ignition Electrode
  • Gas Valve
  • PCB
Full explanation for Red Light