Zehnder CS 50 & CA70

Ideal MVHR systems for renovation projects
and extensions

Retrofit MVHRs: Zehnder ComfoSpot 50, ComfoAir 70

Zehnder’s new retrofit MVHR systems are now available.

Their main advantages:

  • They only need one core through an external wall.
  • They are constant flow MVHR units and not push-pull systems
  • They are Passivhaus certified with good heat recovery
  • Relatively quiet operation

Zehnder ComfoAir 70

Zehnder ComfoSpot 50

De-central single room MVHR

Key parameters:

– Balanced single room MVHR (PH certified)
– 15 – 50 m3/h (4.2 – 13.9 l/s) output
– One 340mm core through external wall needed
– For 335 to 900mm thick walls
– ERV core (heat & humidity recovery)
– Humidity, CO2 and VOC control possible
– Quiet operation

 

The ComfoSpot 50 can switch between 4 fan speed settings::

Fan speed Volume flow Volume flow Thermal efficiency Humidity recovery Power cons. Noise level
[m³/h] [l/s] [%] [%] [W] [dB(A)]
1 15 4.2 85 74 4 5.2
2 25 6.9 76 58 6 14.7
3 40 11.1 69 46 10 23.2
4 50 13.9 62 44 15 29

Zehnder ComfoAir 70

De-central or ducted MVHR

Zehnder ComfoAir 70Key features:

– Can be connected with one 90mm supply duct and one 90mm extract duct to connect one additional supply and extract room.
– 15 – 60 m3/h (4.2 – 16.7 l/s) output
– One 270mm core through external wall needed
– For 275 to 900mm thick walls
– ERV core (heat & humidity recovery)
– Humidity, CO2 and VOC control possible
– Quiet operation – even quieter with supply ducting and extract ducting

 

 

The ComfoAir 70 can switch between 4 fan speed settings:

Fan speed Volume flow Volume flow Thermal efficiency Humidity recovery Power cons. Noise level
no ducting
Noise level
1 duct
Noise level
2 ducts
[m³/h] [l/s] [%] [%] [W] [dB(A)] [dB(A)] [dB(A)]
1 15 4.2 90 84 4 11.0 9.2 2.9
2 25 6.9 83 73 5 23.6 16.3 16.0
3 40 11.1 76 61 9 29.4 24.3 16.2
4 60 13.9 71 54 17 36.4 31.2 22.7

Further Information

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