Medium
4.11 on Ideal Logic+ Combi C

Your boiler is still providing hot water for your taps, but it is not turning on when you ask for central heating.

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

No CH Operation but HW Works OK

Shared across the Logic COMBI2 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 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 4.11: 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

F1View →F2View →L2View →

All 27 fault codes on the Logic+ Combi C

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

4.34.44.54.64.74.84.94.104.124.13Fan FaultFlame LossFlame On Before Gas OnFlow Thermistor FaultFlow/Return ReversedHigh Mains VoltageIgnition LockoutLow Mains VoltageOutside Sensor FaultOverheat LockoutPCB FaultReturn Thermistor FaultRoom Stat FaultSpare PCB Not SetToo Many RestartsWater Pressure

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 →

Is boiler cover worth it?

Break-even maths on monthly cover.

Read →