Most domestic ventilation systems struggle to provide fresh air into habitable spaces. Only ducted systems, like whole house MVHR have a good chance that good indoor air can be rovided by design.
The reason for this problem is that a room with a closed internal door will have very little convection that connects the air to the rest of the dwelling. E.g. CO2 and pollutants in a bedroom will build up over night, whereas the air quality behind the door is still fine. Opening the room door will re-connect that room with the rest of the dwelling.
Cascade MVHR systems overcome this issue through a mechanical solution that reacts to deteriorating air quality, without the need for ducting.
This type of fan is used as part of Cascade MVHR systems and connects habitable rooms into the MVHR system without ducting. It is installed in internal walls of bedrooms, studies, living rooms, etc.
Cascade fans extracts air out of the room, which will draw fresh air from the MVHR unit into the room through the door undercut or other transfer opening. The freeAir Plus is fully automated according to CO2, humidity and temperature readings of the extracted air.
Cascade fans are noise attenuated to minimise cross-talk between the hallway and the respecive habitable room.
Also the fan noise is silenced so much, that it is almost inaudible. At 50 m3/h ventilation rate the noise levels is 19 dB(A).
Like the freeAir 100 MVHR unit, the freeAir Plus fan measures and records the indoor environmental data. It connects via Wifi to your router and you can read out all the data if you want. If not, the system will just work quietly in the background with very little maintenance. Just a yearly dusting off will do.
| Type of system | Cascade fan | |
| Installation rooms | = | Living rooms, bedrooms, studies, etc. |
| Max. air flow | [m3/h] | 70 / 19.4 l/s |
| Min. air flow | [m3/h] | 8/ 2.2 l/s |
| Power supply | 285 – 265 V AC, 45-65 Hz | |
| Fuse rating | 3A | |
| Power consumption | W | Standby → 0.5 W; |
| 30 m3/h → 0.9 W; | ||
| 50 m3/h → 1.4 W; | ||
| 70 m3/h → 2.5 W | ||
| Noise level | dB(A) | 30 m3/h → 13 dB (A); |
| 50 m3/h → 25 dB (A); | ||
| 70 m3/h → 37 dB (A) | ||
| Dimensions | mm | 250 x 250mm |
| Wall thickness internal wall | mm | 100 – 220mm |
| Core through wall | mm | 160mm |
| Control | Intelligent Comfort-control with 5 levels | |
| Temperature range | 0°C bis +40°C | |
| Smart-Home | Connect WiFi; Connect USB; | |
| bluHome Connect (accessory for ModBus, KNX, BACnet, RS232) | ||
| CO2 Control | Automatic | |
| Summer cooling | Automatic, passive | |
| Application | Cascade MVHR systems | |
| Colour | Front cover white or primed for painting |
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