Ravenheat HE120 / HE150 Fault codes & diagnostics

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

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Download the Ravenheat HE120 / HE150 manual The official installation & service manual (PDF) — the exact document these fault codes were verified against. PDF

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Severity at a glance

Each cell = one fault code. Hover to identify.
6 High

All 6 documented codes

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01

Your boiler has attempted to start several times but has failed to light the flame required to produce heat or hot water.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Printed circuit board
04

Your boiler has detected that it is getting too hot and has automatically shut down to prevent any internal damage or safety hazards.

High Engineer only £120-250

Parts commonly replaced

  • High limit thermostat
  • Pump
  • Diverter valve
  • Heat exchanger

Related codes

06

Your boiler is struggling to detect the temperature of your hot water supply, so it has stopped providing hot water to prevent internal overheating.

High Engineer only £120-200

Parts commonly replaced

  • DHW NTC Sensor
  • Wiring harness
12

Your boiler has lost the ability to measure the temperature of the water being used for your heating, so it has shut down to prevent overheating.

High Engineer only £120-200

Parts commonly replaced

  • NTC heating sensor
  • Wiring harness
17

Your boiler has stopped working because it cannot properly clear exhaust gases, which is a necessary safety step before it can fire up.

High Engineer only £180-350

Parts commonly replaced

  • Flue fan
  • Air pressure switch
  • Wiring harness
  • PCB

Related codes

28

Your boiler has stopped working because the amount of water inside your heating system has dropped too low to operate safely.

High DIY-safe £80-120

What to check first

  1. Locate the external filling loop, which is usually a small silver braided hose connecting two pipes under the boiler.
  2. Open the valves on both ends of the hose to allow water into the system.
  3. Watch the pressure gauge on the front of the boiler until the needle reaches the green zone (typically 1.0 to 1.5 bar).
  4. Close both valves tightly and remove the filling loop if required by your specific model instructions.

Parts commonly replaced

  • Pressure Relief Valve
  • Pressure Transducer
  • Expansion Vessel