Most of the time, the heat recovery process occurs via a high-efficiency counterflow heat exchanger that achieves 85 – 95% heat recovery. The unit is also equipped with an air to air heat pump that can heat the supply air when the dwelling requires heating. Combi 302 Polar Top is used in low energy houses as primary heat source, but it can also control additional, supplementary heat sources such as electric radiators.

The heat pump has a reversible cooling circuit and it can therefore also cool the supply air with up to 14 ºC when necessary during the summer. It is not comparable with an air conditioner. The cooling effect of the unit is not as substantial, which is due to its low level of air exchange of approx. 0.5 times/hour. The outdoor air condenses, which results in a reduced air humidity level in the dwelling. The low level of air humidity makes it easier to cope with a high indoor temperature. That is why we call it “Comfort cooling”.

Airflow (see PLANNING DATA below for SEL/SFP values)

Min : 100 m3/h
Max : 430 m3/h

*1 – At ± 250 Pa and 300 m3/h according to EN 13141-7.
*2 – At ± 100 Pa and 300 m3/h according to EN 13141-7.

ATTENTION! When positioning the unit, you should always consider future services and maintenance. It is recommended that you leave a minimum of 60 cm of clear space in front of the unit.

It must be easy to replace filters and it must be possible to replace, for instance, fans and other components.

ATTENTION! The unit must be level to enable proper drainage from the condensate tray.

Condensate drain

ATTENTION! You MUST install a water trap in connection with the condensate drain to ensure that condensate water can drain away. If you set up the unit outside the climate screen, it is important to use a heating cable to prevent the condensate drain from icing up. Frost protection of the unit is the installer’s responsibility.

Capacity

Capacity of standard unit as a function of qv and Pt, ext.

SEL values according to EN 13141-7 are for standard units with ISO Coarse >75% (G4) filters and without heating element. 

Attention! The SEL values are measured and stated as a total value for both fans.

Temperature efficiency

Temperature efficiency for units with counterflow heat exchanger according to EN308 (dry).

Temperature efficiency EN308: ɳt = (tsupply air-tfresh air)/(textract air-tfresh air)

Heat output supply air

Heat output Qc [W] as a function of qv [m3/h] and outdoor air temperature t21 [°C]. In accordance with EN 14511, t11=21°C (extract air)

Heat output is the contribution to room heating added to the fresh air via Combi 302 Polar Top to the supply air. The ventilation loss is the heat output that is lost without heat recovery at the given volume flow air.

Ventilation loss: Dotted curves
Heat effect: Fixed curves

COP (air-air)

Heat output factor COP [-] supply air as a function of outdoor temperature t21 [°C] and volume flow qv [m3/h] in accordance with EN14511 at a room temperature t11 = 21°C

COP according EN14511 is calculated for the heat pump and counter flow heat exchanger combined.

Sound data

Sounddata is for qv = 210 m3/h and Pt, ext = 100 Pa in accordance with EN 9614-2 for surface and EN 5136 for ducts.

Sound output level LWA drops with falling air volumes and falling back-pressure.

At a given distance, the sound pressure level LpA will depend on the acoustic conditions at the installation site.