Error E02

Safety first:

1. If you smell gas evacuate the property immediately, do not operate electrical switches, do not use matches or phones inside, and call the gas emergency number and a Gas Safe engineer from a safe location.

2. If you are at all unsure or uncomfortable, stop and call a Gas Safe registered heating engineer. Do not remove sealed panels or attempt gas valve/electrode replacement unless you are qualified.

Initial checks a homeowner can do (safe, non-invasive):

1. Note the error code and time of occurrence. Try a single reset using the boiler reset button or power cycle at the isolator for 30 seconds. Do not repeat resets many times; repeated attempts can force lockout and may be logged by the boiler.

2. Check that the gas supply to the house appears normal. Light another gas appliance such as a hob or gas fire. If other appliances fail to light, the problem is likely a gas supply issue and you should contact your gas supplier or a Gas Safe engineer.

3. Check the boiler gas isolation valve (usually a lever on the gas pipe into the boiler) is in the open position. Ensure any external LPG supply tank has fuel.

4. Confirm the boiler has mains electrical supply and the display/backlight is normal. Check the fuse and any RCD/MCB protecting the boiler.

5. Check basic boiler conditions: water pressure is within normal range (typically about 1.0–1.5 bar for many systems), condensate pipe is not frozen (in cold weather), and air intake or flue terminals are not blocked by debris, snow, or nesting.

Simple diagnostic observations you can report to an engineer:

1. When you call for heat or after reset, listen for the sequence: fan running, sparking sound, then gas flow noise or ignition. If you hear sparking but no gas flow sound, that suggests the gas valve may not be opening. If you hear nothing before lockout, it could be an ignition/electrical or control fault.

2. If you see any different or additional fault codes or blinking patterns, write them down. Some codes indicate lockout due to false flame or too many resets.

More specific checks and guidance (do not perform if not qualified):

1. Inspect visible wiring and high-voltage lead to the ignition electrode for obvious damage or loose connections. A loose HT lead or corroded connector can stop the spark reaching the electrode.

2. The ignition/flame detection electrode must be correctly positioned and the tip gap is important (manufacturer guidance typically shows around 3 mm). Incorrect gap or damaged ceramic insulator will affect ignition. Repositioning or replacement of the electrode requires removing the boiler front and is a job for a Gas Safe engineer.

3. The gas valve and burner assembly should be checked for operation and correct inlet pressure. This requires a manometer and specific gas safety tools. Do not attempt to adjust or replace the gas valve yourself. Gas valve replacement and combustion checks must be carried out and certified by a Gas Safe engineer.

4. If the boiler indicates false flame or flame loss before lockout, the flame sensing circuit or control box may be faulty and will need professional electronic diagnosis.

When to call a professional and what to tell them:

1. Call a Gas Safe registered heating engineer if the fault persists after the safe checks above, if other gas appliances are affected, if you smell gas, or if you need panel removal, electrode replacement, gas valve work, or combustion/gas pressure checks.

2. When you call, tell the engineer the exact model, the E02 code, what you have already tried (reset, whether other gas appliances work, whether the gas isolation was open, noises heard during attempted ignition), and whether the problem is continuous or intermittent.

Important notes:

1. Many ignition and gas valve repairs require the boiler cover to be removed and gas isolation, and must be done by a Gas Safe engineer. The manufacturer manual and official guidance recommend a qualified engineer for electrode, gas valve, and control box replacement.

2. Do not attempt internal repairs that affect gas or combustion. Safety, correct combustion, and gas tightness must be certified by a professional.

3. Keep records of fault occurrences and any engineer visits for warranty and service history purposes.