E38 Boiler Fault Code: What It Means on Every Brand

The E38 fault code appears on 2 boiler brands — Alpha and Keston — and on all of them it points to the same kind of problem. The details still differ by brand (thresholds, sub-codes, reset procedure), so use the table below to jump to the page for your boiler.

Lockout — engineer likely 2 brands use this code

Which brand is your boiler?

The brand is printed on the front casing. Tap your brand for the full causes, fixes and repair costs.

Brand	What E38 means	Severity	DIY?
AAlpha	The E38 code indicates that your Alpha boiler has repeatedly lost its flame signal while running. Full guide →	Lockout — engineer likely	No
KKeston	The E38 code on a Keston boiler signals a reset key fault — meaning the boiler's internal diagnostics have detected a problem with the reset button or the fascia PCB (the printed circuit… Full guide →	Lockout — engineer likely	No

E38 brand by brand

Alpha E38

The E38 code indicates that your Alpha boiler has repeatedly lost its flame signal while running. In practical terms, the boiler successfully ignites, but something is then causing it to lose confirmation that the flame is still burning — so it shuts down automatically as a safety precaution. A small ionisation electrode sits in the burner and detects the live flame by measuring a tiny electrical current. The moment that current disappears, the boiler cuts the gas supply to prevent any risk of a leak. When this happens again and again, E38 is logged. Important note on how E38 appears on your display: on many Alpha InTec and InTec² models, the live fault code shown on the display is actually E43 (loss of flame rectification), while E38 is the underlying code stored in the boiler's INFO fault history menu — it is the explanation for why E43 keeps occurring. If your engineer reads out E38 from the fault history, or your display shows E43 on a repeated basis, this page covers both situations. Models that log E38 include the Alpha InTec, InTec², InTec GS, InTec S, and E-Tec ranges.

Causes, fixes & costs for Alpha E38 → · All Alpha codes

Keston E38

The E38 code on a Keston boiler signals a reset key fault — meaning the boiler's internal diagnostics have detected a problem with the reset button or the fascia PCB (the printed circuit board sitting behind the front display panel). The boiler cannot confirm the reset button is operating correctly, so it locks out as a safety measure. Keston's own guidance points directly to replacement of the fascia PCB as the remedy. Because this fault sits within the boiler's control electronics, it is not something a homeowner can resolve without the help of a Gas Safe registered engineer.

Causes, fixes & costs for Keston E38 → · All Keston codes

Frequently asked questions

Is the E38 fault code the same on every boiler?

Broadly, yes — on Alpha and Keston the E38 code points to the same class of fault, and the recommended response is similar. Model-specific details such as sub-codes and reset procedures still vary, so follow the page for your own brand.

Can I fix a E38 fault myself?

Not usually. On every brand listed, E38 points to a fault that needs a suitably registered engineer to diagnose and repair. A single reset to rule out a transient glitch is reasonable; repeated resets are not.

Who should I call about a E38 fault?

For gas boilers, a Gas Safe registered engineer — it is a legal requirement for any work on the appliance. If you smell gas at any point, leave the property and call the National Gas Emergency line on 0800 111 999.

General guidance only — not a substitute for professional advice, and not certified by a registered engineer. Any work on a gas appliance must be carried out by a Gas Safe registered engineer. If you smell gas, call 0800 111 999.