Andrews E14 Fault Code: Causes, Fixes & Repair Costs
What does the Andrews E14 fault code mean?
The E14 code on an Andrews water heater or boiler indicates that the appliance has attempted to light the burner but either failed to ignite or could not confirm a stable flame is present. As a result, the boiler locks itself out as a safety precaution. To put this in context within the Andrews E-code series: E12 relates to a differential water flow switch fault (remaining open), E13 to the same switch remaining closed, and E15 to a gas valve command fault — placing E14 squarely between these as an ignition or flame-detection lockout. The boiler will not attempt to fire again until the underlying fault is resolved and the unit is reset. Because repeated failed ignition attempts can allow unburnt gas to accumulate, this code should be investigated promptly rather than reset indefinitely.
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
- Dirty or damaged ignition/flame-sensing electrode Common
Over time, the ignition electrode can accumulate carbon deposits, crack, or fall out of correct alignment. The flame-sensing electrode — sometimes a separate component — can also corrode or become coated, preventing it from confirming to the PCB that a flame is present. Either of these issues will cause the boiler to lock out after its ignition attempts fail.
- Gas supply disruption Common
If the gas supply to the boiler has been interrupted — a closed isolation valve, a prepayment meter that has run out of credit, or low pressure at the meter — the burner simply won't light regardless of how healthy the electrodes and controls are. Air trapped in the gas line after a supply outage can also cause the first few ignition attempts to fail.
- Faulty flame sensor or wiring connection Sometimes
The flame sensor (ionisation probe) tells the control board whether a flame is burning. A corroded sensor, a loose wiring connector, or damaged insulation on the sensor lead can produce false 'no flame' readings, triggering lockout even when the burner is operating correctly.
- Gas valve not opening correctly Sometimes
If the gas valve is failing to open fully — due to a faulty solenoid, internal debris, or wear — insufficient gas reaches the burner and ignition fails. This is distinct from a total gas supply failure and typically requires the valve to be tested under working conditions by an engineer.
- PCB or ignition lead fault Sometimes
The PCB manages the entire ignition sequence: fan proving, gas valve triggering, spark generation, and flame confirmation. A failing PCB or a degraded high-voltage ignition lead can disrupt any one of these steps, causing the sequence to abort and E14 to be displayed.
- Low-voltage electrical disturbance on the control circuit Rare
Intermittent faults on the low-voltage side of the control system — poor earth connections, interference, or a device wired into the circuit that is causing a voltage drop — can confuse the control board during the ignition sequence. This type of fault is particularly difficult to diagnose because it may not appear consistently.
How to fix it
- Check that your gas supply is working DIY safe
Try another gas appliance in your home, such as a gas hob or cooker, to confirm the supply is on. If you have a prepayment meter, check there is sufficient credit. If the supply has recently been interrupted and then restored, air may be present in the line — your engineer can purge this safely.
- Check the boiler's system pressure DIY safe
Look at the pressure gauge on the boiler front. For most Andrews units it should sit between 1 and 1.5 bar when cold. If it is below 1 bar, top it up using the filling loop (two interconnected valves, usually beneath the boiler). Open both valves slowly, watch the gauge rise to around 1.2 bar, then close both valves. Do not overpressurise beyond 1.5 bar.
- Reset the boiler — but only once or twice DIY safe
Locate the reset button (or switch) on the boiler's control panel and hold it for the duration specified in your user guide — typically 3–5 seconds. Allow the appliance a full ignition attempt before deciding whether it has cleared. If it locks out again, do not keep resetting: repeated failed ignition attempts can allow unburnt gas to build up and will not cure the underlying fault.
- If the fault persists, contact a Gas Safe registered engineer Gas Safe engineer
A persistent E14 requires hands-on diagnosis by a qualified engineer. They will inspect and test the ignition and flame-sensing electrodes, check the gas valve operation and gas pressure at the appliance, examine the PCB and ignition lead, and — if the fault is intermittent — systematically disconnect devices from the low-voltage control circuit one at a time to isolate the source. Do not remove the boiler casing or attempt to access any internal components yourself. Verify your engineer's Gas Safe registration at gassaferegister.co.uk before work begins.
Parts you may need
- Ignition electrode assembly · from £35
- Flame sensor (ionisation probe) · from £30
- Ignition lead (HT lead) · from £25
- Gas valve · from £180
- PCB (printed circuit board) · from £280
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 keep resetting the boiler to get hot water while I wait for an engineer?
It is best not to. Resetting once or twice is reasonable to check whether the fault has cleared itself — for example after a brief gas supply interruption. However, if the boiler locks out again each time, further resets are pointless and potentially unsafe: each failed ignition attempt introduces unburnt gas into the heat exchanger. Leave the boiler in its locked-out state and arrange for an engineer as soon as possible.
How much will an E14 repair cost on an Andrews boiler?
For the most common causes — electrode cleaning or replacement, flame sensor swap, or ignition lead — most homeowners pay somewhere between £150 and £400 including parts and labour. If the fault turns out to be the gas valve or PCB, costs can rise to £500 or more once parts and fitting are included, though this is less typical. Emergency or out-of-hours call-outs will attract a premium on top of the repair cost.
What is the difference between the Andrews E12, E13, E14 and E15 codes?
These codes all sit within the same fault-code series on Andrews appliances. E12 indicates the differential water flow switch has remained open when it should have closed; E13 is the opposite — the switch has remained closed when it should be open. E14 points to an ignition or flame failure lockout, where the boiler has tried to light but cannot confirm a flame is present. E15 relates to a fault in the gas valve command signal from the PCB. All four codes require a Gas Safe engineer to diagnose and repair the root cause.
How often should an Andrews boiler be serviced to prevent ignition faults?
Andrews recommend annual servicing as a general rule, though the appropriate interval can vary with the intensity of use — a commercial installation running many hours per day may need more frequent attention. Annual servicing by a Gas Safe registered engineer allows the ignition electrodes, flame sensor, gas valve, and controls to be checked and cleaned before they deteriorate to the point of causing a lockout. It is also a legal requirement that any servicing work is carried out by a competent, registered engineer.