Medium
34 on Chaffoteaux Calydra 100

Your boiler is struggling to detect which setting you have chosen, meaning it cannot reliably switch between providing heating and hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Four position Selector switch (position descriptions provided in manual)

From this model's manual
Verified against the Chaffoteaux/Chaffoteaux Calydra 100 installation & service manual, page 29.
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.

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Related fault codes

30View →31View →

All 5 fault codes on the Calydra 100

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

38394041

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