Vokera Sabre 25 HE Plus Fault codes & diagnostics

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

Combi Natural Gas 25 kW 2005-current
GC Number 47-094-09
Download the Vokera Sabre 25 HE Plus 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 →

Just want the most common Vokera Sabre 25 HE Plus 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

GREEN LED ON every 0.5-secs

Your boiler has paused temporarily because it has detected a minor issue, most likely low water pressure or a brief interruption in the airflow.

Medium DIY-safe £0-120

What to check first

  1. Check the pressure gauge on the front of the boiler; if it is below 1 bar, top it up to 1.5 bar using the filling loop.
  2. Restart the boiler by turning the mode selector switch to the 'OFF/RESET' position and then back to 'ON'.
  3. Check that the outdoor flue pipe is not obstructed by debris or snow.

Parts commonly replaced

  • Air Pressure Switch
  • Pressure Sensor

Related codes

Full explanation for GREEN LED ON every 0.5-secs
RED LED Solid

Your boiler has detected a faulty internal temperature sensor, causing it to shut down as a safety precaution.

High Engineer only £90-160

Parts commonly replaced

  • Primary NTC Thermistor
  • Wiring harness

Related codes

Full explanation for RED LED Solid
Status & diagnostic codes

4 operating states & engineer diagnostics

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

GREEN LED Flashing 8-times a second Status Your boiler has entered an automatic mode where it is adjusting its internal temperature settings to operate more efficiently. GREEN LED ON every 6-secs Status Your boiler is in normal standby mode and is working correctly, simply waiting for you to turn on the heating or hot water. GREEN LED Solid Status Your boiler is working normally and is currently heating your home or providing hot water as requested. YELLOW LED ON every 0.5-secs Diagnostic Your boiler is currently running in a special engineer-only testing mode used to check combustion levels.
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