Vokera Sabre 29HE Fault codes & diagnostics

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

Combi Natural Gas 29 kW 2005 onwards Discontinued
GC Number 47-094-71
Download the Vokera Sabre 29HE manual The official installation & service manual (PDF) — the exact document these fault codes were verified against. PDF

This boiler uses LED flash patterns

Count the flashes in one repeating group before the pause. That number is your fault code. Do not reset until you have noted it. How to read fault codes →

Versions & GC numbers

Which version do you have?

The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.

GC number Appliance (register name) Produced
47-094-71 29HE 2005–present
Just want the most common Vokera Sabre 29HE faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes

All 4 documented codes

Tap any card for details

LED / flash-pattern codes
Red LED flashing every 0.5 seconds

Your boiler has gone into a safety lockout because it is unable to safely clear exhaust gases or has detected an internal temperature issue.

High DIY-safe £120-350

What to check first

  1. Turn the mode selector dial to the OFF (0) position.
  2. Wait for 2 full minutes to allow the system to clear.
  3. Turn the dial back to the 'ON' or heating/hot water position and see if the light stops flashing.

Parts commonly replaced

  • Fan
  • Limit Thermostat
  • Air Pressure Switch
  • Primary NTC Thermistor

Related codes

Full explanation for Red LED flashing every 0.5 seconds
Digital codes
Green LED on every 0.5 seconds

Your boiler has paused because the water pressure is too low or it is struggling to vent air properly.

High DIY-safe £0-180

What to check first

  1. Check the pressure gauge on the front of the boiler.
  2. If the needle is below 1, use the filling loop valves underneath to top up the water until it reaches between 1 and 1.5 bar.
  3. Check if any radiator valves were left closed or if the external flue is blocked by debris.

Parts commonly replaced

  • Air Pressure Switch
  • Venturi Tube
  • Fan

Related codes

Full explanation for Green LED on every 0.5 seconds
Red LED solid

Your boiler has shut down completely due to a safety lockout which could be caused by an electrical fault, a blocked flue, or the system overheating.

High DIY-safe £120-300

What to check first

  1. Turn the mode selector knob to the OFF (0) position.
  2. Wait for exactly 2 minutes for the system to clear the fault.
  3. Turn the selector back to the original position (Hot Water or Heating) and wait for the boiler to restart.

Parts commonly replaced

  • Primary NTC Thermistor
  • Limit Thermostat
  • Fan Motor
  • Air Pressure Switch

Related codes

Full explanation for Red LED solid
Status & diagnostic codes

2 operating states & engineer diagnostics

Not faults — these are normal operating states. Tap to expand.

Green LED flashing rapidly (8/sec) Status Your boiler is currently pre-heating its internal water store to ensure you get hot water quickly, which is a normal feature and not a fault. Green LED on every 6 seconds Status Your boiler is in standby mode and is simply waiting for you to turn on your heating or hot water; everything is working correctly.