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Heat pumps · Error codes · Clivet
L1Clivet

L1 on a Clivet heat pump: Low voltage DC bus protection of inverter module

Short answer

On a Clivet heat pump, L1 means: Low voltage DC bus protection of inverter module. 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 Edge EVO 2.0 EXC (WiSAN-YME 1 S)

The manual says: Low voltage DC bus protection of inverter module.

Likely causes:

  • See Clivet WiSAN-YME manual corrective-action column for this code (not reliably transcribed).

On the Sphera EVO 2.0 (MiSAN-YEE split + SQKN-YEE indoor)

The manual says: DC bus low voltage protection.

Likely causes:

  • See Sphera EVO 2.0 service manual troubleshooting (p.49-105) for this code.

Is it safe?

Switch the heat pump off at its isolator and call an engineer.

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

The manual does not say whether the heat pump stops.

What you can check

  • Read and note the exact code shown on the controller display.
  • Check the heat pump's breaker/isolator at the consumer unit is on.
  • If the breaker has tripped or trips again, leave the unit off and call an engineer; do not keep resetting it.

What the engineer will check

On the Edge EVO 2.0 EXC (WiSAN-YME 1 S)

  • See Clivet WiSAN-YME manual corrective-action column for this code (not reliably transcribed).

On the Sphera EVO 2.0 (MiSAN-YEE split + SQKN-YEE indoor)

  • See Sphera EVO 2.0 service manual troubleshooting (p.49-105) for this code.

Sources

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

Reviewed: 23 September 2026