Unknown
IGNITION LOCKOUT on Main 12 Heat ErP

Main 12 Heat ErP fault code IGNITION LOCKOUT

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Is there gas at gas valve inlet? Is there gas flow from gas valve? Is there at least 18mbar dynamic at gas valve inlet?

From this model's manual
Verified against the Main/Main Bm Main Heat Erp 12 15 18 24 30 Installation Servicing 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 IGNITION LOCKOUT: 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.

All 4 fault codes on the 12 Heat ErP

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

FAN LOCKOUTOVERHEAT LOCKOUTTHERMISTOR

Related guides you might find useful

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 →

New boiler cost 2026

Realistic UK prices for a swap.

Read →