Medium
171 on ECA FELiS FL 50 HM

Your boiler has detected an external alert or safety signal from an accessory like a thermostat or zone controller, which has temporarily stopped the heating.

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

Alarm contact 1 active

From this model's manual
Verified against the Eca Felis Fl 50 Hm installation & service manual, page 61.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check if your external room thermostat or programmer has run out of batteries.Ensure all external controls and smart hubs are switched on and connected to your Wi-Fi.Check for any visible damage to the wiring leading from external controls to the boiler.

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