Error E133

{ "ai_overview": "E133 on a Potterton Assure combi or system boiler is an ignition lockout fault: the boiler has tried to light the burner but has not detected a stable flame and has gone to safety lockout. The code commonly points to a gas supply or ignition/flame-detection issue — examples include loss of gas supply, a frozen or blocked condensate pipe causing the boiler to shut down, failed ignition electrodes or leads, a faulty flame sensing electrode, a sticking or faulty gas valve, incorrect gas valve adjustment, or faults with wiring or the PCB.\n\nSeverity is moderate to high because the code indicates a failure to ignite safely. The boiler locking out protects you from uncontrolled gas flow, so the risk is primarily loss of heating and hot water, but any signs of a gas smell or gas supply problems should be treated as an immediate safety emergency. Some basic checks and resets can be done by a competent homeowner, but any work on gas valves, internal gas components, or electrical wiring must be carried out by a Gas Safe registered (or locally qualified) heating engineer. If simple checks do not resolve the fault, call a professional rather than attempting internal repairs yourself.", "troubleshooting": "Safety precautions:\nIf you smell gas, leave the property immediately, do not use electrical switches, do not smoke or use naked flames and call your gas emergency number (in the UK call 0800 111 999). Isolate electrical supply to the boiler only if safe to do so. Do not attempt to dismantle gas valves, burners, or sealed combustion parts unless you are a qualified gas engineer.\n\nInitial homeowner checks you can do safely:\n1. Check the boiler display and note the E133 and any other stored fault codes and symptoms (e.g. pump running, fan noise, spark/no spark, visible clicking).\n2. Try a controlled reset: follow the manufacturer’s reset procedure once or twice (switch off, wait a minute, switch on or press reset). Do not continually force resets — try 1–2 times to purge air if gas was recently interrupted.\n3. Check gas supply: confirm other gas appliances (hob, fire) work. Ensure the gas meter emergency control valve (ECV) is open and, if you have a prepayment meter, that it is in credit.\n4. Check boiler electrical supply: make sure the boiler fused spur or breaker and the consumer unit haven’t tripped if the boiler display is blank.\n5. Check boiler pressure: ensure system pressure is roughly 1–1.5 bar. Extremely low pressure can affect operation.\n6. Check condensate pipe/trap: in freezing weather an external condensate pipe can freeze and cause lockout. If frozen, carefully pour warm (not boiling) water on the external section to thaw. Also check for visible blockages at the condensate trap if accessible.\n\nBasic diagnostic observations (safe visual checks only):\n1. With the boiler panel off only if you are comfortable and the electrical supply is isolated, visually inspect ignition electrodes and wiring for obvious damage, heavy carbon build-up or disconnection. Dirty electrodes or a fouled flame sensor can prevent flame detection.\n2. Listen during a firing attempt (one reset): you may hear the fan start, pump run, and then clicking from the ignition module or gas valve. No clicking may point to ignition module or ignition lead problems; clicking but no gas flow or a “clanging” gas valve noise can indicate a faulty gas valve.\n3. If the boiler briefly lights then goes out, this suggests flame detection problems (sensing electrode out of position/faulty) or gas composition/pressure issues rather than a complete lack of gas.\n\nSimple maintenance actions a competent homeowner can try:\n1. Reset once or twice after addressing supply issues (meter/credit/thawed condensate). If gas was off and is restored, waiting and attempting 2–3 resets can purge air in the gas line — but avoid repeated resets beyond this.\n2. If you are experienced and it is safe to do so, gently clean lightly soiled ignition and sensing electrodes with a clean, lint-free cloth or very fine abrasive. Ensure power and gas are isolated before removing any covers. Refit and test. If you are not confident, skip this and call a pro.\n\nWhen to call a professional (and what to tell them):\nCall a Gas Safe registered engineer if: resets don’t clear the fault; there is no gas to the boiler but other appliances are okay (possible internal valve fault); condensate thawing didn’t help; electrodes cleaned or replaced by you didn’t fix it; you hear unusual noises from the gas valve; the boiler lights then drops out; or there are any wiring, PCB or gas valve concerns. A qualified engineer will have the tools and gas analysers to test gas pressure and flow, check and set the gas valve, replace ignition electrodes, flame sensors, coils or PCB, and correctly re-calibrate the burner and air/gas mixture.\n\nNotes and practical tips:\nRecord the exact fault code(s), any sounds, and what you have already checked — this speeds diagnosis. Do not attempt to adjust or repair the gas valve, change PCB settings, or alter sealed gas components yourself. Safety first: if in doubt, stop and call a professional.