High
E13 on Biasi Rinnova Adaptive Combi

Your boiler is struggling because there is a significant temperature difference between the water leaving the unit and the water returning to it, often indicating a restriction in the flow of water around your system.

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

Delta T M-R > 40K.

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.

Find a Gas Safe engineer
Search the official register →
Boiler cover options

Avoid the next call-out bill

A cover plan would handle faults like E13: no call-out fees, no surprise bills.

Approved partner
Domestic Appliance Guard
Unlimited call-outs, 24/7 helpline, no price-hike promise
Get a quote →

Affiliate links. We may earn a commission at no extra cost to you.

Related fault codes

E04View →E11View →

All 51 fault codes on the Rinnova Adaptive Combi

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

bPcPdPE01E02E03E04E05E06E07E08E09E10E11E12E14E15E16E17E18E19E20E21E22E23E24E25E26E32E40E42E44E50E62E65E68E77E78E79E89E91E96E97E99hPL1L01LPPOWrench symbol

Related guides you might find useful

Hot water works but heating does not

On a combi it is usually the diverter valve. On a system boiler, the motorised valve.

Read →

No hot water but heating works

Almost always a stuck diverter valve on a combi.

Read →

Banging, kettling or whistling noise

Each noise points to a different fault.

Read →