0 / H Medium

Ideal 0 / H Fault Code

Also written as 0H — same fault.

The Ideal 0 / H fault code means: your boiler is working fine to heat your hot water, but it is failing to send heat to your radiators.. It appears on 1 Ideal 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: The central heating installation is not heated, but the hot water tank (if present) is.
Typical repair cost £120-250 (including labour)

Engineer required

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

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Ideal models that show the 0 / H fault code

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

Source

Ideal 0 / H fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.

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