Preheating of Fresh Air : Fresco SL

Fresco SL : Solar Preheating on Flat Roofs

The Fresco SL solar air heater is designed for mounting on flat roofs to preheat outside air just before it enters the ventilation unit, with no impact on the building’s architecture.

Because it is mounted on spacious flat roofs, the Fresco’s major advantage over wall installations is that it can always be designed to face due South, and inclined at an optimal inclination of 70°, to maximize solar warm air output during the cold season.

How the Solar Collector Works

General Function

Technical Data

Technical Sheet

Fresco SLSI Units [IP Units]
Technical Data
Solar air collector typeTranspired unglazed collector
Working fluidAir only
Main use and purposePreheating of outdoor air
Solar area6 m2 [65 ft2]
Possible airflow range170 m3/h à 1000 m3/h [100 CFM à 600 CFM]
Pressure drop @ maximum throughflow370 Pa [1 in H2O]
Maximum temperature rise above ambient50 °C [90 °F]
Peak solar efficiency, rated90
Weight40 kg [100 lbs]
Absorber panel
Panel materialAluminum alloy 99.8, Temper H18
Absorber panel thickness0.7 mm [0.028 in]
Panel surface treatmentHighly selective VDP coating
Available colors, selectiveblue, black
Absorbtivity in thermal spectrum94%
Emissivity in thermal spectrum≤3%
Panel porosity1-4%
Mounted collector system
Typical distance between 2 rows*390 mm [15.3 in]
Typical inclination to the horizontal70°
Optimal orientationSud ou sud-est
Minimal hieght of the collector above roofline900 mm [36 in]
Required maintenancenone
Freeze protectionN/A
Overheating protectionN/A
Ratings & certifications
Solar Rating Certification Corp. certificate noSRCC 10002111
Test laboratoryFraunhofer ISE, Germany
*Note : Calculate at 45° of latitude

Efficiency Curve of the Solar Collector

Pressure drop curve of the collector

Dimensions of the collector

Project Photos