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Solar Flat Plate CollectorauroTHERM classic VFK 135/2

The solar collector of the auroSTEP plus drain-back systems.

auroTHERM classic VFK 135/2
  • Collect the sun's free energy
  • Dedicated to drain-back solar systems auroSTEP plus
  • Arrangement according to context, number according to needs
  • Sturdy construction for long-lasting performance and efficiency
The solar thermal flat plate collector auroTHERM classic VFK 135 is dedicated to auroSTEP plus drain-back system for domestic hot water production. Drain-back technology has the advantage of providing unbeatable resistance during excessively sunny or cold periods, preventing any stress on the solar collector and increasing its lifespan. Depending on the region and the level of sunlight, it can cover 70% or more of the heat needed to heat domestic hot water for free. Its sleek and flat design with the stable structural glass allows 91 % of solar energy to pass through, while the side insulation ensures reliable heat transfer. These solar flat plate collectors can be installed vertically or horizontally to meet your specific needs, mounted on or integrated into the roof, on a sloped surface or on a terrace – always with dedicated and reliable frames or fixing brackets.
auroTHERM classic VFK 135/2
Ideal for:
  • Heating
  • Hot water

Technical data table overline

Technical data table headline

auroTHERM classic
VFK 135/2 VD
Collector Minimum YieldCollector Minimum Yield525 kWh/m²a
Aperture Collector Surface AreaAperture Collector Surface Area2,35 m²
Gross Collector Surface AreaGross Collector Surface Area2,51 m²
Collector Standby TemperatureCollector Standby Temperature210 °C
Collector Efficiency η₀Collector Efficiency η₀73,6 %
Collector Transmission FigureCollector Transmission Figure91 %
Collector Absorption FigureCollector Absorption Figure95 %
Collector Emission FigureCollector Emission Figure5 %
Collector Heat Transmission Coefficient 1Collector Heat Transmission Coefficient 13,643 W/m²K
Collector Heat Transmission Coefficient 2Collector Heat Transmission Coefficient 20,016 W/m²K²