Low
dF on Viessmann Vitodens 200-W WB2C 35kW System

Your boiler is still heating your home, but it has lost contact with the room sensor for one of its heating zones, so that zone may not reach the temperature you have set.

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

Control mode without room influence: Lead break, room temperature sensor, heating circuit 3 (with mixer)

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W Wb2c Service 5692857 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 dF: 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

dAView →dHView →

All 82 fault codes on the Vitodens 200-W WB2C 35kW System

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

4C9A9b9C9E9F1018202830384044485051585990919293949899A7b0b1b5b7b8bAbbbCbdbEbFC1C2C3C4C5C6C7C8CdCECFd6d7d8dAdbdCdddEE0E1E3E4E5E7E8EAEbECEdEEEFF0F1F2F3F8F9FAFCFdFEFF

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 →

Boiler service cost

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

Read →