Low
Two red lights flash rapidly on Worcester Bosch Worcester 25/30 HE

Your boiler is currently in a manual service mode rather than standard operating mode because the adjustment dial on the control panel has been set to the minimum or maximum position.

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

Mode switch is set to MAX or MIN using the mode adjuster tool.

From this model's manual
Verified against the Worcester Boiler 25si And 28si 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

Locate the small rotary mode adjuster dial on the boiler control panel, often hidden behind a drop-down flap.Using a flat-head screwdriver, gently turn the dial out of the MAX or MIN position to the central 'Auto' or 'Normal' setting.Observe the lights to ensure they stop flashing rapidly and return to a steady state.

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 Two red lights flash rapidly: 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 guides you might find useful

Yellow or orange flame — CO safety

Safety-critical — turn off, read this.

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 →