Calefa Heat Interface Units

Developed in Denmark, the home of District Heating Units and project proven in Europe, Calefa sets new standards for domestic hot water delivery in terms of its responsiveness, efficiency and ease of installation.

  • BESA and KIWA tested

  • Circa 6,000 units sold each year and growing

  • Unique bypass control makes Calefa the most efficient unit on the market

  • Supplied, commissioned and maintained by Wavin

District heating is a sustainable and efficient way to heat homes

District heating is one of the most important elements in the transition to greener energy forms, general energy optimization and, the future in dependence on fossil fuels.

The UN estimates that 70% of the world's population will live in cities by 2050. Global urbanisation is thus putting pressure on both city design and the design of the buildings in which people live and work. Increasing amounts of pollution and noise in cities are already together with a need for energy saving technologies defining the way we design buildings, so that we can maintain our ever-present desire and need for a good and healthy indoor climate while maintaining a high comfort level.

Key benefits of district heating:

  • An efficient and sustainable way to heat homes and businesses than traditional methods, such as oil or gas boilers.

  • It can help to reduce carbon emissions and other pollutants.

  • It is a reliable source of heat, even in cold weather.

  • It can be used to heat both homes and businesses.

    If you are looking for a more sustainable and efficient way to heat your home or business, district heating is a great option.

Heat interface units are one of the elements in Wavins' focus on indoor climate, which today includes complete solutions for underfloor heating, ventilation, and district heating.

Calefa II Features and benefits

  • Adaptive learning: After just two weeks, Calefa will have learnt the consumption, making it a market leader in efficiency through annual volume weighted average return temperature.
  • Easy to use electronic display: User friendly display for both commisioning and daily ise
  • Connected by Sentio: Control the domestic hot water through the Sentio app.
  • Built-in weather compensation: The outdoor temperature controls the supply temperature resulting in high energy efficiency.
  • Wireless outdoor sensor: Connect multiple units with up to 40 m range.
  • Domestic hot water prioritization: Shave peak times and let Calefa prioritize hot water supply over home heating with no loss of comfort.
  • Fast commissioning

Product portfolio

Calefa V: Indirect unit ensures hydraulic separation between the primary and secondary circuit.

Calefa S: Direct unit provides internal blending to reduce the primary flow temperature, making it ideal for UFH and LTHW systems.

Visit your local country to see product portfolio and technical details

Automatic weather compensation

The Wavin Calefa Heat Interface Unit automatically adjusts hot water temperature based on outside air using a single wireless sensor.

This weather compensation saves energy (up to 5%) and simplifies installation: less wiring, faster setup, and lower costs.

One sensor works for multi-unit buildings, reducing investment and maintaining a clean exterior.

The sensor's 40-meter range covers various building sizes.

Adaptive learning

Calefa II learns residents' hot water use and automatically adjusts to only heat water when needed.

It gathers data for 2 weeks and predicts usage patterns.

If no hot water is used for a while, Calefa II stops heating until needed, reducing standby energy waste.

This saves energy and money while ensuring hot water is always available when needed.

Domestic hot water prioritisation

Calefa II prioritises hot water for peak usage times (like mornings) in homes and apartments.

It temporarily pauses heating to maintain hot water flow, boosting network capacity by 50%.

This eliminates the need for a hot water tank, saving space and money.

Fast commissioning

Calefa II simplifies hot water and heating system setup in homes and apartments.

Installation is fast with automatic configuration for most systems, reducing complexity and errors.

This saves time, improves comfort for residents, and simplifies management for everyone involved

Easy to use electronic display

Calefa's electronic display simplifies comfort.

Residents get real-time system status and can easily adjust hot water temperature.

Facility managers can remotely guide residents for optimal heating, saving everyone time.