2-in-1 function


Thermal performance testing for solar air collector; Pressure drop test; Time constant test; Visual inspection; Internal pressuretest; Rupture or collapse test; Stagnation temperature; Exposure test; Externalthermal shock; Internal thermal shock; Rain penetration; Freeze resistance; Mechanical load; Impact resistance test using steel ball; Final inspection. All above listed tests of the standard EN12975-1:2006+A1:2010 and ISO 9806:2017 were passed successfully in accordance with the criteria.


The Solar Keymark is a voluntary third-party certification mark for solar thermal products, demonstrating to end-users that a product conforms to the relevant European standards and fulfills additional requirements. It is widely spread across the European market and beyond. The Solar Keymark is a quality label.

Standard function

Functional principle

The sun shines on the special heating absorption board and the surrounding air absorbs heat. Nakoair® solar air collector/ heater takes in air at the bottom of panels, and through a special construction, the air is heated in the sun catching the most heat and then delivered into the room. The heated fresh air is blown into the house by a fan, driven by photovoltaic panel.

 It has two series with different functions:

OS10/OS20/OS30: Standard Function

⚫Heating outdoor fresh air

Preheating outdoor fresh air, ventilator turns and bring in the heated fresh air. This function can be used in spring, autumn and winter. Applicable to all models.


OS22/OS32/OS42: 2-in-1 function

⚫Heating outdoor fresh air

⚫Heating indoor air internal circularly mode. It is possible to use only air intakes that heat fresh outdoor air, and don't use the air outlet that heat indoor air.

It can keep heating the room air and increasing the room temperature,  prevent people from wet or cold or smog air. This mode is the best way to heat the room. Applicable to OS22/32/42.

When the outdoor temperature is too low, just open the air inlet indoor to keep heating the indoor air. Just close the air inlet indoor to introduce and heat the fresh air outdoor.