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Heat pumps · Error codes · Carrier
8Carrier · AquaSnap / AquaSnap Plus 30AWH (R410A inverter monobloc, 2010-2018 generations)

8 on a Carrier AquaSnap / AquaSnap Plus 30AWH: Unit capacity mismatch

Short answer

On a Carrier heat pump, 8 means: Unit capacity mismatch. The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause.

Reviewed 23 September 2026 · 1 source

What it means

The manual says: Unit capacity mismatch.

Likely causes:

  • Capacity setting mismatch between boards/controller.

Is it safe?

Does the heat pump stop?Yes
Engineer needed?Yes

The heat pump stops until the fault clears or is reset.

What you can check

  • Note the code/LED pattern and the model from the rating plate, then contact a heat pump/refrigeration engineer.
  • Check the heat pump's breaker/isolator at the consumer unit is on.

What the engineer will check

  • Check capacity/configuration parameters.

Who to ask for: refrigeration / heat pump engineer.

Certification: Electrical competence for work inside the unit.

What you might notice

Sources

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

Reviewed: 23 September 2026