TradeAssistIQHome

Riello NXHM fault H7

Voltage protection

Heat pump

What it means

Voltage protection triggered due to power supply issues or main control board defect.

Likely causes

  1. Power supply input out of available range
  2. Power off/on cycled rapidly in short time
  3. Circuit defect part of main control board is defective

Where to start

  1. Check whether the power supply input is in the available range
  2. Check if power was cycled rapidly

The full answer, free

  • The readings and component tests from the manual
  • How to put it right, step by step
  • The manual page for this fault (page 66), right under the answer
Ask about H7 freeCreate a free account

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