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error Ideal

Error Code F5

Return Thermistor Fault — fault within return water temperature sensor circuitry.

? What Causes This

Incorrect thermistor resistance measurements or wiring interruptions between it and the PCB.

How to Fix It

  1. Confirm accurate readings from multimeter tests at specified temperatures and replace faulty components.
  2. Rectify wire connections that provide continuity issues causing communication problems with sensors.

Source: page 55 of the official manual

From the manual

Manual page 55 — Ideal error F5

This error code appears in:

Ideal Boilers I 24