Heating curve (weather compensation)

A heating curve, also called weather compensation, links the outdoor temperature to the flow temperature. When it is warmer outside the system supplies cooler water; when it is colder, warmer water.

• The heat pump runs at the lowest sufficient temperature, so it works more efficiently and evenly.
• Room temperature fluctuates less and manual adjustments are needed less often.
• A curve set too high increases running costs; set too low, the rooms do not warm up in cold weather.

The curve is first set at commissioning according to the design outdoor temperature and the type of heat emitters, and then fine-tuned based on how the house behaves during the first heating season. Mitsubishi Electric ECODAN controllers support weather compensation and additional modes. We commission the system with appropriate settings and explain how to adjust them so that heating is comfortable and economical.

A well-set curve is especially important for underfloor heating, which responds slowly to changes, so frequent manual temperature changes do not suit it.

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