Unknown
EF on Viessmann Vitodens 242-F FB2B

Viessmann Vitodens 242-F FB2B fault code EF

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

The flame is lost immediately after it has built (during the safety time).

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 242 F Fb2b 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 EF: 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 89 fault codes on the Vitodens 242-F FB2B

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

0A0b0C0d0F4C9A9C9E9F101820283038404448505158599294A0A1A2A3A4A6A7A8A9b0b1b4b5b7b8bAbbbCbdbEbFC1C2C3C4C5CdCFd6d7d8dAdbdCdddEdFE0E1E2E3E4E5E6E7E8EAEbECEdEEF0F1F2F3F7F8F9FAFCFdFEFF

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 →