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Heat pumps · Error codes · Trianco
F03Trianco

F03 on a Trianco heat pump: PFC Fault

Short answer

On a Trianco heat pump, F03 means: PFC Fault. The manual does not say whether the heat pump stops. An engineer is needed to fix the cause. The wording differs by model range — each is shown below.

Reviewed 23 September 2026 · 3 sources

What it means

On the Activair High Temperature R290 (5/9/15/22kW)

The manual says: PFC Fault.

Part involved: compressor driver / inverter board.

Likely causes:

  • Power factor correction fault.

On the Activair R290 Indoor (3.2kW wall hung / 5kW floor standing)

The manual says: Pre-Charge Failure.

Part involved: compressor driver / inverter board.

Likely causes:

  • The PFC circuit protection.

On the Activair Pro (AI) R290 6/12/17kW

The manual says: Pre-Charge Failure.

Part involved: compressor driver / inverter board.

Likely causes:

  • PFC circuit protection activated.

Is it safe?

Does the heat pump stop?Not stated
Engineer needed?Yes

The manual does not say whether the heat pump stops.

What you can check

  • Note the exact code shown on the controller (a photo helps) and report it to your installer or the manufacturer's service line.
  • Check the heat pump's supply breaker/isolator at the consumer unit is on (do not open any casing).

What the engineer will check

On the Activair High Temperature R290 (5/9/15/22kW)

  • Restart the unit.
  • Check if the power supply connection and voltage are stable.
  • Replace the compressor driver board.

Who to ask for: heat pump electrical / inverter.

Certification: Electrical competence; manufacturer-trained heat pump engineer.

On the Activair R290 Indoor (3.2kW wall hung / 5kW floor standing)

  • Check the PFC switch tube short circuit or not.

Who to ask for: heat pump electrical / inverter.

Certification: Electrical competence; manufacturer-trained heat pump engineer.

On the Activair Pro (AI) R290 6/12/17kW

  • Check whether the PFC switching transistor is short-circuited.

Who to ask for: heat pump electrical / inverter.

Certification: Electrical competence; manufacturer-trained heat pump engineer.

What you might notice

Sources

A code explains what the controller detected, not a confirmed root cause.

Reviewed: 23 September 2026