High
121 on ECA FELiS FL 50 HM

Your boiler is struggling to get the water in your radiators up to the required temperature, meaning your heating may feel lukewarm or fail to warm up properly.

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

Heating circuit 1 flow water temperature not reached

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.

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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