Boiler displays A07 and will not fire; often associated with incorrect temperature readings or sensor faults.

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Open-circuit flow NTC sensor, Shorted flow NTC sensor, Wiring harness fault to NTC, PCB input fault

Safety first: Isolate electrical power before removing the boiler casing. Components may be hot.

Power cycle: Turn the boiler off for 30 seconds and back on. If A07 clears temporarily and returns, a sensor fault is likely.
Engineer checks:
- Measure resistance of the flow NTC sensor at known temperatures and compare with Ferroli specifications.
- Inspect the NTC connector and wiring for corrosion or damage.
- Replace the flow NTC sensor if readings are out of range or intermittent.
- If sensor and wiring are good, test and possibly replace the main PCB.

Hard 4/5

Flow NTC Temperature Sensor

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