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Heat pumps · Error codes · Trianco
Er12Trianco · Activair R32 (S700 / S1200 - FG 9007 / FG 9012)

Er12 on a Trianco Activair R32: High compressor exhaust gas temperature protection

Short answer

On a Trianco heat pump, Er12 means: High compressor exhaust gas temperature protection. 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: High compressor exhaust gas temperature protection.

Part involved: pressure switch / compressor discharge-suction.

Likely causes:

  • Refrigerant undercharged.
  • Reasons as Er05.

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 is not blocked by debris/snow and has its required clearances.

What the engineer will check

  • Add some refrigerant.
  • Similar corrections as Er05.

Who to ask for: refrigeration.

Certification: F-gas certified refrigeration engineer (REFCOM or equivalent).

What you might notice

Sources

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

Reviewed: 23 September 2026