An indirect substation is used when district heating network conditions, such as pressure and temperature, do not allow direct connection. When a substation is connected indirectly, a heat exchanger provides energy-efficient heat transfer. It also ensures that the primary network supply side and the secondary building installation side remain safely separated. 

In this way, the building application works regardless of pressure or temperature variations in the district heating network (hydronic balancing) and is safe from pipe breaks or leaks.

Danfoss indirect substations are self-contained units that are generally wall-mounted. They can support single or multiple heating circuits, with or without domestic hot water production on the primary or secondary side.

These advanced solutions are also available with an electronic controller for weather compensation. This ensures easy and energy-efficient operation while simultaneously allowing central monitoring and energy consumption transparency.

Features and benefits

Advanced solutions available also with an electronic controller for weather compensation

Indirect substations with Micro Plate™ heat exchangers provide energy efficient heat transfer

Smaller, lighter, more efficient: Danfoss' compact substation DSA1 Mini

Learn how the station is installed, as well as tips and tricks for commissioning and maintenance.

Product range

  • Indirect heating

    A substation for indirect heating has a heat exchanger separating the primary flow from the secondary flow. Indirect substations are recommended for PN16-networks and higher pressure classes. Substations in this category are normally supplied with connection pipes for a domestic hot water cylinder on the primary side for the fitted constructions, and on the secondary side for the welded constructions.

  • Indirect heating and domestic hot water

    A substation for indirect heating has a heat exchanger separating the primary flow from the secondary flow. Indirect substations are recommended for PN16-networks and higher pressure classes.

  • Indirect or direct heating and domestic hot water cylinder

    Substations for indirect heating have a heat exchanger separating the primary flow from the secondary flow. Indirect substations are recommended for PN16 networks and higher pressure classes. Substations for direct heating have no heat exchanger separating the primary flow from the secondary flow and are recommended for maximum PN10 or PN6 networks. The domestic hot water is heated in a cylinder by the district heating water flow in a coil within the cylinder.

  • DSA - Danfoss Station Advanced Compact

    Find more technical information about DSA - Danfoss Station Advanced Compact.

  • DSP - Danfoss Station Pre-engineered

    Find more technical information about DSP - Danfoss Station Pre-engineered.

Documents

Type Name Language Valid for Updated Download File type
Operating guide District heating substations English Multiple 29 Nov, 2017 4.0 MB .pdf
Brochure Specifying the right district heating substation makes commercial sense English Multiple 04 Mar, 2015 2.4 MB .pdf

Tools and apps

Case studies

  • In Helsinki a total of 667 addresses in a mix of large and small buildings and apartments have had the Leanheat software installed.
    Leanheat makes buildings smart

    In Europe, 30 percent of all energy consumption goes to heat or cool buildings. Danfoss has the solution to lower energy usage and improve indoor climate by adding a digital element: Leanheat software.

  • Solar heating plant reduces CO2 emissions by 15,700 tonnes annually
    Solar heating plant reduces CO2 emissions by 15,700 tonnes annually

    The world’s largest solar heating plant in Silkeborg, Denmark harnesses energy to heat the homes and workplaces of 40,000 citizens. It supplies 18-20% of the annual heat consumption in the city of Silkeborg, Denmark, which has an ambitious target of CO2 neutrality in heat production by the year 2030.

  • District energy as the heating and cooling solution in Teknopark Istanbul, Turkey

    Building: Office
    Application: Production of heating, cooling and domestic hot water
    Challenge: Design and construct customized district energy solutions for all buildings on the park
    Solution: Danfoss  designed and constructed 3 pre-assembled DSE substations containing control valves for the heating, cooling and domestic hot water, heat meters, self-acting controllers and electronic controllers connected to a central Building Management System. 

  • District heating compact stations in Mikado House, Orestaden, Denmark

    Building: Office
    Application: Production of heating and domestic hot water
    Challenge: Design and construct a customized compact district heating station
    Solution: Danfoss designed and constructed a pre-assembled station according needs and helped save 14 days of construction work

  • Modernized district heating in a hospital, Belgrade, Serbia

    Building: Hospital
    Application: Heating + Domestic Hot Water production by district heating substations
    Challenge: Modernize old and inefficient heat and hot water system
    Solution: 58 fully equipped prefabricated substations

  • Renovation of an apartment building with flat stations, Hamburg, Germany

    Until 2014, the apartments in this multi-family building located in the Hamburg suburb of Bergedorf were heated using electrical water heaters and supplied with domestic hot water using electrical instantaneous water heaters. Now, after the renovation, a block heating station in the basement of the building provides heating distributed via flat stations installed in the stairwell and used for decentralized domestic hot water. Tenants were able to stay in their apartments throughout the renovation process.