Intergas F009 Fault Code: Causes, Fixes & Repair Costs
What does the Intergas F009 fault code mean?
The F009 fault code on Intergas boilers signals an internal fault within the burner controller — the electronic unit responsible for managing the ignition sequence and overall combustion process. In practice, this means the boiler's 'brain' has detected something wrong with itself or its core control circuitry, and the boiler has shut down as a safety measure. Because the burner controller is so central to safe boiler operation, this is one of the more serious fault types on the Intergas range and cannot be resolved by a homeowner reset alone. A Gas Safe registered engineer will need to diagnose and repair the fault.
General guidance only — not a substitute for professional advice, and not certified by a Gas Safe engineer. Always have your specific appliance assessed by a qualified professional. Any gas work must be carried out by a Gas Safe registered engineer. If you smell gas or suspect carbon monoxide, leave the property and call the National Gas Emergency line on 0800 111 999.
Common causes
- Failed or damaged PCB / burner controller board Common
The most likely cause of F009 is an internal failure of the burner controller PCB itself. This could be a burned-out component, a failed microprocessor, or a cracked solder joint — any of which can cause the controller to report an internal fault and prevent the boiler from firing.
- Water ingress or corrosion on the board Common
A boiler leak — even a minor one from a nearby component — can allow moisture to reach the PCB. Water on a live circuit board causes short-circuits and corrosion that can permanently damage the controller. If you notice any damp around the boiler casing, this is a likely culprit.
- Wiring or connector faults Sometimes
Loose, chafed, or corroded wiring harnesses feeding the burner controller can cause it to register an internal fault even if the board itself is intact. Vibration over time can work connections loose, and poor earthing can cause erratic signals that mimic a controller failure.
- Power surge damage Sometimes
A mains voltage spike — from a lightning strike, a grid fault, or a large appliance switching on — can damage the sensitive electronics on the PCB. This is more common in properties without surge-protected spur sockets on the boiler supply.
- Faulty sensor or peripheral component masking as a controller fault Rare
Although F009 points squarely at the burner controller, Intergas boilers can occasionally report an internal fault when a connected sensor (such as a thermistor or fan speed sensor) is providing bad data. An engineer needs to rule these out before condemning the PCB.
How to fix it
- Attempt a single boiler reset DIY safe
Press and hold the reset button on the boiler's control panel as described in your user manual. If the boiler fires up and runs normally, monitor it over the next 24 hours. If F009 returns quickly or the boiler fails to restart at all, do not keep resetting — move on to the next step.
- Check your mains power supply DIY safe
Confirm the boiler's fused spur is switched on and the fuse has not blown. Also check your consumer unit (fuse board) for any tripped breakers. A brown-out or brief power interruption can occasionally trigger a controller fault that clears after a clean power cycle.
- Check for any visible water leaks around the boiler DIY safe
Look around the boiler casing, nearby pipework, and underneath the unit for signs of dripping water or damp patches. Do not open the boiler casing yourself, but note any leaks you find and report them to the engineer — moisture near the PCB is an important diagnostic clue.
- Do not attempt further resets or open the boiler Gas Safe engineer
Repeatedly resetting a boiler with an internal controller fault will not fix the underlying problem and may mask important diagnostic information for the engineer. Opening the boiler casing or interfering with wiring or components is not safe for a homeowner and must not be attempted.
- Call a Gas Safe registered engineer to diagnose the fault Gas Safe engineer
An engineer will attend and use a multimeter to check voltages and continuity across the PCB, inspect the wiring harnesses and connectors, and test associated components such as the fan and thermistors to rule out peripheral causes. Only once the root cause is confirmed will they advise on repair or replacement of the burner controller.
- Allow the engineer to repair or replace the burner controller PCB Gas Safe engineer
If a minor issue such as a cracked solder joint or a loose connector is found, a competent engineer may be able to carry out a targeted repair. If the board is burned, corroded, or water-damaged, full replacement of the PCB is the safer and more reliable outcome. The Intergas burner controller board (part numbers 074447 or 074448) is a readily available spare and the swap typically takes one to three hours. Post-replacement, the engineer will run the boiler through a full commissioning check to confirm correct operation.
Parts you may need
- Intergas Burner Controller PCB (074447 / 074448) · from £95
- Wiring harness / loom · from £35
- NTC thermistor sensor · from £18
- Fan assembly · from £85
The exact spare depends on your boiler's GC number (on the data badge). Check this against the part before buying.
Typical repair cost
Expect to pay roughly £280–£600, depending on the underlying cause.
Frequently asked questions
Can I reset an Intergas F009 fault myself?
You can try a single reset using the button on the control panel — occasionally a transient power issue clears this way. However, if the fault returns or the boiler does not restart, further resets will not help and a Gas Safe engineer is needed. F009 is an internal controller fault that almost always requires professional diagnosis and repair.
How much does it cost to fix an Intergas F009 fault in the UK?
Most homeowners pay between £280 and £600 for an F009 repair, depending on whether a minor fix (such as resoldering a joint or replacing a connector) is sufficient or whether a full PCB replacement is needed. The Intergas controller board itself is relatively affordable at around £75–£115 for the part, but labour — typically one to three hours — makes up the bulk of the bill. Regional rates vary, with London and the South East usually at the higher end. If the fault turns out to be a peripheral component such as a fan or sensor rather than the PCB itself, the cost can be at the lower end of the range.
Is it worth repairing an Intergas boiler with an F009 fault, or should I replace it?
If your boiler is under ten years old and otherwise in good condition, a PCB repair or replacement is usually worthwhile — it can restore reliable operation for several more years at a fraction of the cost of a new boiler. If the boiler is older, has a history of breakdowns, or the repair quote exceeds roughly half the cost of a new equivalent boiler, replacement is often the better long-term investment, particularly given the efficiency gains of a modern unit.
Could the F009 code be caused by something other than the PCB?
Yes, and a good engineer will always check this first. Faulty sensors (such as a thermistor giving out-of-range readings), a failing fan that is not reaching the correct speed, or damaged wiring can all cause the burner controller to report an internal fault. In these cases, replacing the cheaper peripheral component resolves the F009 without the need to touch the PCB at all. This is one reason why a proper diagnostic visit — rather than simply ordering a new board — is the right first step.