High
E15 on Biasi Rinnova Adaptive Combi

Your boiler has sensed that the water returning from your radiators is hotter than the water leaving the boiler, which usually means the water isn't flowing through the system correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Return temperature > Delivery temperature (>10 °C)

Shared across the Rinnova Adaptive range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E13View →E14View →E16View →

All 51 fault codes on the Rinnova Adaptive Combi

Seeing a different code? Every code this model can display, in one place.

bPcPdPE01E02E03E04E05E06E07E08E09E10E11E12E13E14E16E17E18E19E20E21E22E23E24E25E26E32E40E42E44E50E62E65E68E77E78E79E89E91E96E97E99hPL1L01LPPOWrench symbol

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