E.04-.13 Boiler Fault Code: What It Means on Every Brand

The E.04-.13 fault code appears on 2 boiler brands — Baxi and Remeha — 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 E.04-.13 means	Severity	DIY?
BBaxi	The E.04-.13 code is a permanent lockout fault on Baxi boilers, meaning the boiler has shut itself down completely and will not restart until the root cause is resolved and the fault is… Full guide →	Lockout — engineer likely	No
RRemehashown as E.04.13	The E.04.13 code appears on Remeha boilers when the control system detects that the fan is not behaving as expected. Full guide →	Lockout — engineer likely	No

E.04-.13 brand by brand

Baxi E.04-.13

The E.04-.13 code is a permanent lockout fault on Baxi boilers, meaning the boiler has shut itself down completely and will not restart until the root cause is resolved and the fault is manually cleared. It tells you that the boiler's fan system has failed — either the fan rotor has jammed and can no longer spin, the fan motor has burned out, or the electrical wiring feeding the fan has been damaged or has come loose. The fan plays a dual safety role: it draws fresh air into the combustion chamber so gas can burn correctly, and it expels waste flue gases afterwards. Without a functioning fan the boiler's safety controls will not allow any gas to reach the burner, which is exactly why this fault causes a full lockout rather than a temporary error.

Causes, fixes & costs for Baxi E.04-.13 → · All Baxi codes

Remeha E.04.13

The E.04.13 code appears on Remeha boilers when the control system detects that the fan is not behaving as expected. This could mean the fan is not spinning freely, is running erratically, or is operating at an unexpectedly high speed. Because the fan is responsible for moving combustion gases safely out through the flue, any deviation from normal behaviour triggers an automatic safety lockout — the boiler will refuse to fire for heating or hot water until the underlying problem is resolved and the fault is cleared. The '04' portion of the code identifies this as a fan and airflow subsystem fault, while '13' points to the specific condition of irregular or over-speed fan operation.

Causes, fixes & costs for Remeha E.04.13 → · All Remeha codes

Frequently asked questions

Is the E.04-.13 fault code the same on every boiler?

Broadly, yes — on Baxi and Remeha the E.04-.13 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 E.04-.13 fault myself?

Not usually. On every brand listed, E.04-.13 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 E.04-.13 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.