A07
Ferroli
Return Temperature Sensor Fault
Error A07, unit may start and stop repeatedly, temperature fluctuates strongly.
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Safety Warning
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.
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Possible Causes
Open or shorted return NTC sensor, Loose sensor connection, Damaged wiring harness, Faulty PCB sensor input
How to Fix / Troubleshooting
Safety: Isolate electrical power before removing covers.
- 1. Locate return NTC: On Ferroli combination water heaters, the return sensor is usually on the return pipe to the heat exchanger. Confirm it is firmly clipped and making good thermal contact.
- 2. Inspect wiring: Follow the sensor cable back to the PCB. Reseat the connector and check for damage along the cable.
- 3. Compare sensor readings: If you have a multimeter and the skills, measure resistance of both flow and return NTCs at the same temperature; they should be similar. Replace the return NTC if it is clearly out of range.
- 4. PCB evaluation: If a new sensor does not resolve A07, the main control board may be defective and should be replaced by a qualified technician.
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Repair Difficulty
Medium
3/5
Required Part
Return NTC Sensor
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