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Heat pumps · Error codes · Trianco
F101Trianco

F101 on a Trianco heat pump: DC Fan 1 Phase Loss Prot

Short answer

On a Trianco heat pump, F101 means: DC Fan 1 Phase Loss Prot. 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 · 2 sources

What it means

On the Activair Commercial R290 50kW (FG9550)

The manual says: DC Fan 1 Phase Loss Prot.

Part involved: DC fan motor / fan driver board.

Likely causes:

  • System 1 fan failed to start.

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

The manual says: Driver (Fan) Phase Loss Fault.

Part involved: DC fan motor / fan driver board.

Likely causes:

  • Fan motor phase loss detected.

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).
  • Check the outdoor unit grille/coil is not blocked by leaves, debris or snow (do not open the casing).

What the engineer will check

On the Activair Commercial R290 50kW (FG9550)

  • Check if the system 1 fan line is normal.

Who to ask for: heat pump electrical.

Certification: Electrical competence for work inside the outdoor unit.

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

  • Check that fan cables are connected properly and securely.

Who to ask for: heat pump electrical.

Certification: Electrical competence for work inside the outdoor unit.

What you might notice

Sources

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

Reviewed: 23 September 2026