SI 18TU

SI 18TU

SI 18TU

Highly efficient brine-to-water heat pump for indoor installation. 18 kW heat output.

The power is in the earth.

The SI 18TU is a highly efficient brine-to-water heat pump with 18 kW heat output. Installed indoors, it is the most efficient solution for newly built single family homes and apartment blocks, as well as renovations, with a heated living area of up to 400 sqm. The universal design means that domestic hot water preparation can also be connected with this series.

  • Naturally quiet. Sound-optimised through insulated metal casing and double vibration-isolated compressor.
  • Low operating costs. High seasonal performance factors thanks to economizer and sensor monitoring of the refrigeration circuit for high operational reliability and integrated thermal energy metering.
  • Expansion options. Bivalent or bivalent-renewable operation, distribution systems with mixed and unmixed heating circuits (e.g. underfloor heating and radiators). Even more efficient room temperature control Smart-RTC+.
  • Future-orientated. Use of load-variable tariffs or self-produced PV-electricity possible: SmartGrid Ready.
  • Intelligent. Eligible for funding in existing buildings thanks to high efficiency. Suitable for use in new builds for compliance with the German federal energy efficiency ordinance (EnEV) and Renewable Energy Heat Act (EEWärmeG).
  • Adjustable. Including for special applications, such as use with a heat source temperature up to –10 °C.

Technical Data.

Energy efficiency class with 35 °C flow temperature: A++


Energy efficiency class with 55 °C flow temperature: A++


Heat output B0/W35: 17,5 kW


COP B0/W35: 4,7


Lower operating limit heat source (heating operation): -5 Grad


Upper operating limit heat source (heating operation): 25 Grad


Max. flow temperature: 62 Grad


Sound pressure level in 1 m: 38 dB(A)


Width: 650 mm


Height: 845 mm


Depth: 665 mm


Weight: 163 kg


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