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Heat pumps · Error codes · Vaillant
S.111Vaillant

S.111 on a Vaillant heat pump: Cooling: Compressor shutdown The cooling demand is met, the demand is ended by the system control. The compressor is switched off

Short answer

On a Vaillant heat pump, S.111 means: Cooling: Compressor shutdown The cooling demand is met, the demand is ended by the system control. The compressor is switched off. The heat pump keeps running. The wording differs by model range — each is shown below.

Reviewed 23 September 2026 · 2 sources

What it means

On the aroTHERM plus (VWL ../6 A)

The manual says: Cooling: Compressor shutdown The cooling demand is met, the demand is ended by the system control. The compressor is switched off.

Part involved: Heat pump control (status/Live Monitor).

When it shows: Cooling: Compressor shutdown The cooling demand is met, the demand is ended by the system control. The compressor is switched off.

Likely causes:

  • Operating status reported by the heat pump control (not a fault in itself).

On the flexoTHERM exclusive (VWF ../4)

The manual says: Cooling: Compressor shutdown.

Part involved: Heat pump control (status/Live Monitor).

When it shows: See official description.

Likely causes:

  • Operating status reported by the heat pump control (not a fault in itself).

Is it safe?

Does the heat pump stop?No
SeverityInformation only
Engineer needed?No

The heat pump keeps running.

Resetting itself: yes - status changes automatically with operating state.

Manual reset: not applicable.

What you can check

  • Operating status only - no action needed. If heating or hot water is not being delivered for a long period, note the status code and tell your installer.

What the engineer will check

  • None required unless heating/hot water is not delivered; then review status history, settings and application limits.

Who to ask for: Vaillant-trained heat pump installer/engineer (MCS-certified installer).

Certification: MCS installer certification; Vaillant product training recommended.

Sources

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

Reviewed: 23 September 2026