BoilerFaultCodes Last 28 days · Real search data
Most-searched boiler fault codes
The fault codes UK boiler owners actually look up — ranked by what's most searched on the site. Each entry links to the full plain-English explanation, repair cost estimate, and severity.
| # | Code | What it means | Severity | Searches |
|---|---|---|---|---|
| 1 | A08 Ferroli Bluehelix Pro RRT | Your boiler has detected that the water inside it has become dangerously hot and has shut itself down to prevent damage. ~£120-250 | High | 1 clicks 1 impressions |
| 2 | A1 Worcester Bosch 24i / 28i Junior | Your boiler has detected that it is running without enough water inside, which is often caused by a leak or a pump that has jammed or failed. ~£180-350 | High | 0 clicks 1 impressions |
| 3 | Limescale Build-up Ariston E-Combi One Combi | Your boiler has detected that limescale is building up inside the part that heats your tap water, so it is limiting its own temperature to protect itself from further damage. ~£150-300 | Medium | 0 clicks 1 impressions |
| 4 | E.04.03 Baxi 400 Combi 2 | Your boiler has shut down because it thinks the water inside has become far too hot or a temperature sensor has malfunctioned. ~£120-250 | High | 0 clicks 1 impressions |
| 5 | E119 Baxi Duo-tec Combi HE | Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely. ~£80-150 | High | 0 clicks 1 impressions |
| 6 | E125 Baxi Duo-tec Combi HE | Your boiler is struggling to pump water around your heating system correctly, usually because the water pressure is too low or the pump is blocked. ~£150-350 | High | 0 clicks 1 impressions |
| 7 | FAN Baxi Combi 80e | Your boiler has detected an issue with the internal fan that clears waste gases, meaning the system has safely shut down to prevent any hazards. ~£220-£450 | High | 0 clicks 1 impressions |
| 8 | Boiler On light on Baxi Solo 3 40 PF | Your boiler is receiving power and has been told to turn on by your thermostat, so it should be operating normally. | Low | 0 clicks 1 impressions |
| 9 | Fan On Baxi Solo 3 40 PF | Your boiler has stopped working because it cannot confirm that the internal fan, which clears exhaust gases, is receiving power. ~£120-250 | High | 0 clicks 1 impressions |
| 10 | Overheat Baxi Solo 3 PFL | Your boiler has become too hot and has automatically shut itself down to prevent damage or safety issues. ~£100-280 | High | 0 clicks 2 impressions |
| 11 | Fan On Baxi Solo PF | Your boiler has stopped working because it cannot confirm that the internal fan, which clears exhaust gases, is receiving power. ~£120-250 | High | 0 clicks 1 impressions |
| 12 | E97 Biasi Rinnova Adaptive Combi | Your boiler is not receiving enough electrical power from the mains supply to operate safely and has shut down as a precaution. ~£100-£350 | High | 0 clicks 1 impressions |
| 13 | 03 Chaffoteaux Talia Green 25 | Your boiler is trying to start, but it cannot sense a steady flame, so it has safely shut itself down to prevent gas from building up. ~£120-250 | High | 0 clicks 1 impressions |
| 14 | J6-01 Daikin D2CND | Your boiler is getting too hot too quickly because water isn't flowing through the system properly or the pressure has dropped too low. ~£100-£250 | High | 0 clicks 1 impressions |
| 15 | 2.7bar Glow-worm 30ci Plus | Your boiler has too much water inside it, causing the pressure to rise to an unsafe level. ~£60-180 | Medium | 0 clicks 2 impressions |
| 16 | S.109 Glow-worm Energy System | Your boiler is currently in a temporary power-saving standby mode and is operating normally. | Low | 0 clicks 1 impressions |
| 17 | S.109 Glow-worm Energy7 System | Your boiler is currently in a temporary sleep mode and is functioning exactly as it should. | Low | 0 clicks 1 impressions |
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