Riello NXHM fault HF

Suction temperature sensor (th) error (EEprom related)

Heat pump

What it means

Suction temperature sensor error attributed to EEprom or inverter module board failure.

Likely causes

  1. EEprom parameter error
  2. EEprom chip part broken
  3. Inverter module board broken

Where to start

  1. Check EEprom parameters
  2. Check EEprom chip integrity
  3. Check inverter module board

The full answer, free

  • How to put it right, step by step
  • The manual page for this fault (page 66), right under the answer

Safety: Isolate the heat pump and any backup heater, and give the inverter capacitors time to discharge before you open the electrics. Anything on the refrigerant circuit needs F-gas certification.

From the Riello manual for the NXHM. Check the model on the data plate before you order parts.

Other Riello NXHM fault codes