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Heat pumps · Error codes · Trianco
F105Trianco · Activair Commercial R290 50kW (FG9550)

F105 on a Trianco Activair Commercial R290 50kW: DC Fan 1 Overcurrent Prot

Short answer

On a Trianco heat pump, F105 means: DC Fan 1 Overcurrent Prot. The manual does not say whether the heat pump stops. An engineer is needed to fix the cause.

Reviewed 23 September 2026 · 1 source

What it means

The manual says: DC Fan 1 Overcurrent Prot.

Part involved: DC fan motor / fan driver board.

Likely causes:

  • System 1 fan running current is too large.

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

  • Check if the system 1 fan rotor is locked.

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