Medium
E0 on Sime Murelle HE 110R

Your boiler is struggling to move heat away from the unit efficiently, causing it to slow down to protect itself from overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Reduced capacity operation (Δt between delivery and return over 40°C)

From this model's manual
Verified against the Sime/Sime Murelle He 110r installation & service 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 fault requires 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 E0: 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

E11View →E12View →

All 10 fault codes on the Murelle HE 110R

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

E1E2E3E4E5E6E7E8E9

Related guides you might find useful

Banging, kettling or whistling noise

Each noise points to a different fault.

Read →

Hot water works but heating does not

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

Read →

Boiler keeps cutting out

Lockout fault with a reset-needed pattern.

Read →