Vokera AL10 Fault Code: Causes, Fixes & Repair Costs
What does the Vokera AL10 fault code mean?
The AL10 code means your Vokèra boiler attempted to light but could not confirm a flame was present. The boiler shuts itself down as a safety precaution, leaving you without heating or hot water until the fault is cleared. It is worth knowing that Vokèra uses slightly different code formats across its range: the Linea displays this as code 10, the Compact shows it as A01, and Mynute HE models show AL10 — but all point to the same ignition or flame-sensing failure. On some Vokèra models AL10 can also be triggered by an overheating condition, so an engineer may need to check the pump, thermistors, and system circulation as well as the ignition components.
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
- Faulty ignition electrode or leads Common
The ignition electrode can erode over time, and the high-voltage leads that carry the spark can crack or develop poor connections at their terminals. Either problem prevents a reliable spark from forming, so the boiler gives up and locks out. This is the single most frequently replaced component when AL10 appears.
- Gas supply interruption Common
If the gas supply to the property is temporarily interrupted — for example during local network works or if a prepayment meter has run out — the boiler will attempt to ignite, fail to sense a flame, and trigger AL10. Check that other gas appliances such as a hob or gas fire are working before assuming the boiler is at fault.
- Flame sensor fault or dirty electrode tip Common
Even when a flame does light briefly, a contaminated or damaged flame-sensing electrode may fail to detect it. The boiler then interprets this as no flame and shuts down. Carbon deposits or oxidation on the electrode tip are typical culprits.
- Blocked or frozen condensate pipe Sometimes
A blocked or frozen condensate pipe can prevent the boiler from operating and may contribute to AL10 appearing, particularly in cold weather. Vokèra's own documentation for the Mynute HE explicitly references the condensate sensor as part of this fault code.
- Gas valve not opening correctly Sometimes
The gas valve controls fuel flow to the burner. If it fails to open fully — due to an internal fault, corrosion, or an electrical issue — insufficient gas reaches the burner and no stable flame can be established. Gas valve faults require professional diagnosis.
- PCB (printed circuit board) fault Sometimes
The PCB orchestrates ignition sequencing and flame-signal processing. A failing PCB may send incorrect signals to the ignition system or misread the flame sensor input, causing AL10 even when the physical ignition components are in good condition.
- Overheating condition triggering lockout Rare
On certain Vokèra models, AL10 sits alongside other overheat-related fault codes. If the pump has failed, the system is heavily sludged, or a thermistor is reading incorrectly, the boiler may overheat and lock out in a way that presents as AL10. An engineer would check circulation and temperature sensors in this scenario.
How to fix it
- Check that your gas supply is working DIY safe
Turn on a gas hob ring or another gas appliance to confirm gas is reaching your home. If there is no gas supply to any appliance, contact your gas supplier rather than resetting the boiler. If other appliances work normally, the supply is not the issue.
- Inspect the condensate pipe for freezing or blockage DIY safe
In cold weather, the plastic condensate pipe that runs outside the boiler can freeze solid. Carefully pour warm (not boiling) water over the visible external section of the pipe to thaw it. Never use a naked flame. Once thawed, reset the boiler and monitor it.
- Reset the boiler once or twice DIY safe
Press and hold the reset button (usually labelled R) for 3–5 seconds until the fault code stops flashing, then release. On models with a mode selector, turn it to the OFF/RESET position and then back to your desired mode. Allow the boiler a full ignition attempt before concluding the fault has cleared. Repeat once more if the first attempt fails, but do not continue resetting repeatedly as this can mask a serious fault.
- Do not attempt to inspect or adjust gas components yourself Gas Safe engineer
Work on the gas valve, ignition electrode wiring, PCB, or any internal boiler component must only be carried out by a Gas Safe registered engineer. Attempting this yourself is illegal and dangerous.
- Call a Gas Safe registered engineer Gas Safe engineer
If the fault persists after the checks above, book a Gas Safe registered engineer. They will use a multimeter and combustion analyser to test the ignition leads, electrode, flame sensor, gas valve, and PCB in turn to identify the root cause. You can verify an engineer's credentials at gassaferegister.co.uk. Ask them to carry out a full service at the same time if one is overdue, as this can prevent repeat faults.
Parts you may need
- Ignition electrode · from £107
- Ignition cable / lead · from £112
- Gas valve · from £514
- PCB (printed circuit board) · from £320
- Condensate trap / siphon · from £35
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 £150–£400, depending on the underlying cause.
Frequently asked questions
Can I fix the Vokèra AL10 fault myself?
The only safe DIY steps are confirming your gas supply is on, thawing a frozen condensate pipe, and resetting the boiler once or twice. Any inspection or replacement of internal components — the ignition electrode, leads, gas valve, or PCB — must be done by a Gas Safe registered engineer. Attempting gas work yourself is illegal under UK law and puts you and your household at serious risk.
How much does it typically cost to fix a Vokèra AL10 fault in the UK?
Most homeowners pay somewhere between £150 and £400 all-in, depending on which component is at fault. An ignition electrode or lead replacement is usually the least expensive fix, while a gas valve replacement will sit toward the upper end of that range. A PCB replacement can cost £450–£550 or more and is worth considering carefully on an older boiler — at that price, a new boiler may offer better long-term value.
Why does my Vokèra show code 10 or A01 instead of AL10?
Vokèra uses different code formats across its product range. Code 10 on the Linea and A01 on the Compact both describe the same ignition or flame-sensing failure as AL10 on the Mynute HE. The underlying diagnosis and repair approach is identical regardless of how the code is displayed on your particular model.
How can I prevent the AL10 fault from coming back?
An annual boiler service by a Gas Safe engineer is the most effective prevention. During a service, the engineer cleans the ignition electrode, checks lead connections, inspects the flame sensor, and tests combustion — addressing the small issues that eventually cause faults like AL10. Repeatedly resetting the boiler without having it investigated is a warning sign that should not be ignored, as it can allow an underlying problem to worsen.