Trianco Activair R32 S700, S1200 fault ER03

Water flow switch failure

Heat pump

What it means

Fault detected on the water flow switch, indicating insufficient or no water flow detected.

Likely causes

  1. Low water flow
  2. Faulty flow switch
  3. Pump failure
  4. Air lock in system

Where to start

  1. Check water flow switch operation
  2. Verify pump is running
  3. Check for air in system

The full answer, free

  • 1 more check in order
  • How to put it right, step by step
  • The manual page for this fault (page 11), right under the answer

Safety: Isolate the outdoor unit 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 Trianco manual for the Activair R32 S700, S1200. Check the model on the data plate before you order parts.

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