Low
dU on Ideal Independent + Combi 24

Your boiler is currently in a manual service mode used for internal checks and is not indicating a broken part.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

DIVERTER VALVE IN MID-POSITION FOR SERVICE ROTATE KNOBS FULLY CLOCKWISE TURN POWER OFF AND ON RESTART BOILER

From this model's manual
Verified against the Ideal/Ideal G101 Ideal Independent Plus Combi 30 4734928 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.

DIY fix possible

Turn the boiler off at the isolation switch or fused spurWait 10 secondsTurn the boiler back on to reset the control sequence

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

Avoid the next call-out bill

Monthly cover means no unexpected bills when your boiler breaks down.

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

UFView →L2View →F2View →

All 21 fault codes on the Independent + Combi 24

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

F1F2 or Fn or LnF3F4F4 or L4F5F5 or L5F6F7F9 or L9 or F8 or L8FAFUL1L2L4L4 or F4L5L5 or F5L6LC

Related guides you might find useful

Boiler service cost

What a UK service costs and what a proper one includes.

Read →

Is boiler cover worth it?

Break-even maths on monthly cover.

Read →

When to replace your boiler

7 signs repair isn't worth it anymore.

Read →