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Heat pumps
Heat pumps · Error codes · Kronoterm
Low-Comp-tempKronoterm · TERMOTRONIC-controlled heat pumps (legacy WP / WPL / WPLV water-water, brine-water, air-water)

Low-Comp-temp on a Kronoterm TERMOTRONIC-controlled heat pumps: Compressor temperature too low; after three indications the PZ PROG is activated

Short answer

On a Kronoterm heat pump, Low-Comp-temp means: Compressor temperature too low; after three indications the PZ PROG is activated. 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: Compressor temperature too low; after three indications the PZ PROG is activated.

Part involved: compressor temperature.

Likely causes:

  • Allowed minimum compressor temperature reached.

Is it safe?

Does the heat pump stop?Yes
SeverityFault — needs a manual reset once the cause is fixed
Engineer needed?Yes

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

Manual reset: After fixing the cause restart by holding ENTER for 3 s.

What you can check

  • Note the exact message shown on the TERMOTRONIC display.
  • Reset the device from the controller, as the manual allows.

What the engineer will check

  • Authorised service.

Who to ask for: heat pump engineer.

What you might notice

Sources

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

Reviewed: 23 September 2026