E.02-.48 Boiler Fault Code: What It Means on Every Brand

The E.02-.48 fault code appears on 2 brands — Baxi and Remeha — and it does not mean the same thing on each. The same two or three characters can signal a pressure problem on one boiler and an ignition fault on another, so identify your brand first and use the table below to jump to the right page.

Up to: Lockout — engineer likely 2 brands use this code Meaning differs by brand

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.02-.48 means	Severity	DIY?
BBaxi	The E.02-.48 fault code (also displayed as A.02.48 on some Baxi models) indicates that the boiler has failed to successfully configure or establish communication with a paired external… Full guide →	Lockout — engineer likely	Some checks
RRemehashown as E.02.48	The E.02.48 code is a full lockout on Remeha Ace-series boilers (Tzerra Ace, Avanta Ace, Quinta Ace and similar). Full guide →	Lockout — engineer likely	No

E.02-.48 brand by brand

Baxi E.02-.48

The E.02-.48 fault code (also displayed as A.02.48 on some Baxi models) indicates that the boiler has failed to successfully configure or establish communication with a paired external control device — such as a wireless thermostat, smart controller, or RF receiver. This is a locking error, meaning the boiler shuts down completely and will not restart until the fault is resolved and the boiler is reset. The underlying sub-code .48 represents a full configuration failure, extending beyond the general control bus connection error seen in .45, and points specifically to the boiler being unable to complete the pairing or configuration handshake with the external device.

Causes, fixes & costs for Baxi E.02-.48 → · All Baxi codes

Remeha E.02.48

The E.02.48 code is a full lockout on Remeha Ace-series boilers (Tzerra Ace, Avanta Ace, Quinta Ace and similar). To understand it, it helps to know how Remeha structures its fault codes: the letter prefix tells you the severity — A.xx.xx is a warning, H.xx.xx is a blocking fault, and E.xx.xx is a lockout, meaning the boiler has shut itself down completely and will not restart without intervention. The number group 02.48 identifies a Function Group Configuration Fault, specifically that the boiler's main control unit cannot find or communicate with the SCB (System Control Board) expansion PCB — an additional circuit board fitted to the boiler to handle extra functions such as zone control or extended heating circuits. Because the boiler cannot resolve this configuration mismatch, it locks out as a safety measure. This is the lockout-level equivalent of the same underlying fault that appears as A.02.48 (warning) or H.02.48 (blocking) at lower severity thresholds.

Causes, fixes & costs for Remeha E.02.48 → · All Remeha codes

Frequently asked questions

Is the E.02-.48 fault code the same on every boiler?

No. E.02-.48 means different things on different brands — see the table above. Always identify your boiler's brand (it is printed on the front casing) before acting on any advice about the code.

Can I fix a E.02-.48 fault myself?

On some brands there are safe homeowner checks first — typically system pressure, the condensate pipe in cold weather, and a single reset. Where the code is a simple pressure or reset condition, that may be all it needs. Never open the boiler casing yourself.

Who should I call about a E.02-.48 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.