E00.04 Medium

Remeha E00.04 Fault Code

Also written as E0004 — same fault.

The Remeha E00.04 fault code means: your boiler has detected a disconnected sensor on the return pipe, which prevents it from accurately measuring the temperature of the water coming back into the system.. It appears on 1 Remeha model in our database.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description: TReturn Open
Typical repair cost £120-220 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Remeha models that show the E00.04 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Remeha E00.04 fault code information on this page is sourced and cross-checked against the official Remeha service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026