Heat pump sensor calibration and offset: when is it needed

Over time, a sensor may show a slight deviation from the actual value. Some controllers offer a calibration offset feature.

First, verification

Before applying an offset, the reading should be compared against a reliable reference instrument.

Small, constant deviation

This can be corrected with a calibration parameter if the manufacturer allows it.

Large or unstable deviation

This may indicate a faulty sensor, a bad connection, or a wiring problem and should not simply be covered by an offset.

Documentation

Every calibration change must be documented so that it is known for future service.