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error Ideal

Error Code F4

Flow Thermistor Fault — flow temperature sensor malfunctions.

? What Causes This

Improper resistance values in the thermistor, connection breaks or wiring defects with the PCB.

How to Fix It

  1. Check expected resistance levels for temperatures and replace faulty thermistors if found inconsistent readings.
  2. Review and repair wires between the thermistor and board connections for continuity and ensure no breaks/damage exist.

Source: page 54 of the official manual

From the manual

Manual page 54 — Ideal error F4

This error code appears in:

Ideal Boilers I 24