High
F1 on Viessmann Vitodens 100-W B1HC-19

Your boiler has temporarily stopped working because it has gotten too hot inside, usually due to low water pressure or trapped air in the system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Burner in a fault state, Max. flue gas temperature exceeded, Check heating system fill level. Check circulation pump. Vent the system. Press "Reset" (see page 50).

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 100 W B1hc B1kc 19 35 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F2View →F4View →F5View →

All 29 fault codes on the Vitodens 100-W B1HC-19

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

0C5A101830385051525859A3A9b0b7b8E3E5F0F2F3F4F8F9FAFCFdFF

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