Worcester Bosch F0 287 Fault Code: Causes, Fixes & Repair Costs
What does the Worcester Bosch F0 287 fault code mean?
The F0 fault code on Worcester Bosch boilers signals an internal component failure detected by the boiler's control system. The three-digit sub-code that follows narrows down which part of the system is at fault. Sub-code 287 sits within the 280s range, which generally points to internal electronic or control board issues — most commonly a problem with the PCB (printed circuit board) or associated wiring. When the boiler detects this fault, it will typically lock out and you may lose heating, hot water, or both. The fault indicator LED and sometimes the RESET button will flash on affected models. Other F0 sub-codes you may encounter include F0 237 (which can appear alongside power interruption events and may indicate a PCB or mains supply issue) — if you see that code repeatedly, an engineer should test both the incoming power supply and the PCB itself. Sub-codes in the 280s range are consistently linked to internal electronics, so F0 287 should be treated as a control board fault until an engineer proves otherwise.
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 Common
The PCB is the boiler's main control board, responsible for coordinating every function from ignition to modulation. A failed PCB is the most common root cause of F0 faults in the 280s sub-code range. It can fail due to age, component burnout, moisture ingress, or a power surge. When it does, the boiler locks out and throws an internal fault code like F0 287.
- Wiring fault or loose connection Common
Damaged wiring, a corroded connector, or a harness that has vibrated loose can disrupt communication between the PCB and other components. This can trigger an F0 fault because the control board receives an unexpected or absent signal. Wiring issues are more likely on older boilers or where previous repair work has been carried out.
- Power surge or interruption Sometimes
A sudden mains voltage spike or an extended power cut can corrupt the PCB's internal logic or damage sensitive components. If your home recently experienced a power cut or if other appliances were affected at the same time the fault appeared, this is worth noting when you speak to an engineer.
- Gas valve fault Sometimes
In some cases, an F0 code can be linked to the modulating gas valve, the gas valve relay, or the burner control unit. A gas valve issue may present alongside irregular flame signals or ignition lead problems. This is a safety-critical component and must never be inspected or adjusted by anyone other than a Gas Safe registered engineer.
- Faulty sensor sending erroneous data Rare
A temperature sensor, flow sensor, or other monitoring component that has failed and is sending out-of-range data to the PCB can cause the control board to log an internal fault. The PCB may interpret the rogue signal as an internal error and lock the boiler out as a precaution.
How to fix it
- Note the exact code on the display and record any relevant circumstances DIY safe
Before doing anything else, write down the full code as shown — 'F0 287' — and make a note of when it appeared, whether heating or hot water cut out at the same time, and whether there was a recent power cut or power surge in your home. This information will help a Gas Safe engineer diagnose the fault more quickly.
- Attempt a single reset DIY safe
Press and hold the RESET button for approximately three seconds, then release. Some Worcester Bosch models require you to hold it for up to ten seconds. If the boiler fires up and runs normally, monitor it closely. If the F0 287 code returns — either immediately or within a short time — do not reset again. Repeated resets on an internal electronics fault will not resolve the underlying problem and could mask important diagnostic information.
- Check your gas supply is working DIY safe
Confirm that other gas appliances in your home (such as a gas hob or gas fire) are working normally. If they are not, contact your gas supplier or the National Gas Emergency Service on 0800 111 999. If your gas supply is fine, the fault is internal to the boiler.
- Do not remove the boiler casing or inspect internal components Gas Safe engineer
Opening the boiler casing to inspect wiring, test the PCB, or examine the gas valve is not safe for a homeowner and is likely to invalidate your boiler warranty. All internal diagnosis on an F0 287 fault must be carried out by a Gas Safe registered engineer with the appropriate tools and training.
- Call a Gas Safe registered engineer to carry out a full diagnosis Gas Safe engineer
Because F0 287 points to an internal control or electronics fault, a Gas Safe engineer is required to proceed. They will use specialist diagnostic equipment to test the PCB, check wiring harnesses and connectors, inspect sensors, and test the gas valve and ignition components. Based on their findings they will advise whether a repair or component replacement is needed, or whether boiler replacement is more cost-effective given the boiler's age.
Parts you may need
- Replacement PCB (control board) · from £180
- Gas valve (modulating) · from £95
- Wiring harness · from £45
- NTC temperature sensor · from £18
- Ignition lead set · from £22
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 £250–£500, depending on the underlying cause.
Frequently asked questions
Can I fix Worcester Bosch F0 287 myself?
No. While you can safely attempt one reset and check that your gas supply is working, F0 287 is an internal electronics fault that requires a Gas Safe registered engineer to diagnose and repair. Opening the casing, testing the PCB, or touching any wiring or gas components without the correct qualifications is both dangerous and likely to void your warranty.
How much does it cost to fix a Worcester Bosch F0 287 fault in the UK?
Most people with an F0 287 fault end up paying between £250 and £500, with PCB replacement — the most common repair — typically costing £300–£550 including parts and labour. A gas valve replacement is usually £180–£220. If the fault turns out to be a simple wiring connection issue, the cost will be lower. Note that a full heat exchanger replacement or other major component can cost significantly more, but this is rarely the cause of an F0 287 fault.
Should I replace my boiler instead of repairing an F0 287 fault?
It depends on your boiler's age and the repair quote you receive. As a rough guide, if your boiler is under 10 years old and the repair is under £400, repair is usually worthwhile. If the boiler is approaching 15–16 years old and the repair quote is substantial, replacement with a modern A-rated model may be more economical in the long run, especially given the improved efficiency of newer condensing boilers.
Is F0 287 a gas leak? Do I need to evacuate?
F0 287 itself is not a gas leak warning — it is an internal electronics fault code. However, if at any point you smell gas, you should stop using the boiler immediately, avoid operating any electrical switches, open windows and doors, leave the property, and call the National Gas Emergency Service on 0800 111 999. Do not return until the property has been declared safe.