Combi 302 Polar Top

Specifications & Technical Data

Combi 302 Polar Top is a ventilation unit with heat recovery that is typically used in large single-family dwellings.

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


Dimensions (W x D x H) 900 x 604 x 808 mm
Weight 85 kg
Plate type casing Aluzinc steel plate, white powder coating RAL9016
Heat exchanger type Polyethylenterephthalat counterflow heat exchanger
Fan type EC, constant volume
Filter class Greencycle ISO Coarse > 75% (G4)
Compressor type Piston compressor
Refrigerant R134a
Refrigerant filling 700 gr.
Duct connections Ø160 mm
Condensate drain PVC Ø20 x 1,5 mm
Supply voltage 230V 50/60 Hz
Max. input/power 1,8 kW / 7,8 A
Standby power 3W
Tightness class IP31
Ambient temperature -20 / +40 °C
External leakage < 0,54 % (*1)
Internal leakage < 1,71 % (*2)
Heat loss classification T2

*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.


All dimensions are in mm.

1: Fresh air
2: Supply air
3: Extract air
4: Discharge air
5: Condensate drain
6: Electric supply


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.

The unit makes little noise and produces only weak vibrations, but you should still take into account potential vibrations that can spread from the unit to individual building components. In order to separate the unit from its foundation, it is therefore recommended that you install vibration absorbers under the unit. There should be approx. 10 mm distance to other building components and to permanent fixtures.

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 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.


The CTS602 control system is an advanced control system with many settings options. The control system is supplied with factory default settings that can be adapted to the operational requirements in order to achieve best possible operation and utilisation of the unit.

The HMI Touch panel provides an overview of the current operation of the unit, and the structure of its menu makes it easy to navigate for both user and installer. There is an option for selecting between 2 front page images for the main screen.

External communication
The CTS602i control unit communicates by default with Modbus RTU RS485 communication. A CTS system using this form of communication can easily be connected to the unit.

Functional overview CT602 control panel
Function overview   +Standard
Filter guard The time-controlled filter guard notifies you when it is time to change the filter. Can be set between 30 and 180 days. +
Operating mode Can be set to run Auto according to set values ​​or set to run in heating or cooling mode. +
Stepless regulation The four ventilation stages can be set steplessly 20-100%, with different values ​​for supply air and extract air. +
Moisture management Built-in humidity control can be set to run high ventilation mode when there is high humidity (when you are in the shower) and low ventilation mode if the humidity in the home becomes too low. +
Active cooling The unit can be set to cool the supply air in the summer if needed. When the heat pump cools, the heat is deposited in the hot water tank, so that you get “free” hot domestic water when the unit is in cooling mode. +
Low outdoor temperature It is possible to lower the ventilation when the outside temperature is low, to avoid that the humidity inside becomes too low. +
CO2 management It is possible to control the ventilation level according to the home’s CO2 level.
Temperature settings The temperature settings are used by the controller to regulate the operation of the entire system. +
Frost protection The control has an automatic function for defrosting the heat exchanger if ice should form in it. +
Frost protection Polar The Polar model has a built-in anti-freeze pre-heater to protect the counter-flow heat exchanger so that it does not get ice. +
Frost protection EHD The control can control an EHD damper, which is used if the outside air comes via a roof hood. +
Hot domestic water Compact P produces the hot domestic water via the air/air heat pump in the ventilation part. +
Pause domestic hot water It is possible to pause hot water production if, for example, for a period not at home. In this way, energy is saved. +
Antifreeze hot water To protect the hot water tank, it is equipped with a frost protection function. +
Electricity supplement hot water

If the demand for hot water is so great during periods that the heat pump cannot keep up, an electric supplement can be switched on to help heat the hot domestic water.

Scalding protection The control has a built-in scalding protection, which ensures that the hot domestic water does not become too hot and could scald the users. +
Anti-Legionella The control has an Anti-Legionella treatment of the hot domestic water, which can be activated manually or automatically. +
Anode Electronically monitored anode. Notifies when it’s time to replace it, extending the life of the hot water tank.  
SHW preheating tank An additional hot water tank SHW can be connected to the GEO geothermal heat pump and preheat the hot domestic water to 45 ºC before it enters the Compact P hot water tank. +
Hot domestic water If the Compact P is ordered with a solar coil, the GEO ground source heat pump can be connected to the Compact P hot water tank and help produce the hot domestic water. A good solution if there is a large need for domestic hot water and there is no space for a SHW container. +
Weekly schedule A weekly plan can be made with different settings depending on the use of the home. +
Smart Grid Compact P GEO is approved for Smart Grid solutions, where the electricity company determines the electricity consumption and thus the operating costs. +
User selection 1 Used if you want to override the unit’s operation via a potential-free signal. Used e.g. if an extractor hood is connected to the system. +
User choice 2 Used as user selection 1, but at the same time has an output signal that can be used e.g. to control a damper. +
Event log Logs events in the control as well as error messages and warnings. +
Read out data All current values ​​in the plant’s operation can be read out. Most often used for troubleshooting. +
Emergency stop ventilation You must not switch off the ventilation, as this can cause damage to the unit, duct system and, in the worst case, the home. But it may be necessary to briefly switch off the ventilation, e.g. due to an emergency notification. +

Further information about all the functions can be found in the unit’s Software and Assembly instructions.