Hello dear forum,
We are using a Zehnder ComfoAir Q350. Unfortunately, it has had some issues with the "installation" from the start. First, the wrong settings were applied, and then the interior doors were too airtight. After the ventilation technician visited about five times since summer, it is now running reasonably well. Although the air quality in the bedroom still feels as if we have no ventilation, according to the technician everything is set up correctly.
Now that the weather has turned quite cold recently, we have noticed significant condensation on the windows in some areas. Especially in the bedroom and also in the open living-dining area. The technician said this is normal in a new building – however, due to the ventilation system and underfloor heating, we only have about 25% humidity. With an additional humidifier (Venta), we manage to reach almost 40%.
Question: Shouldn’t a ventilation system automatically remove moisture inside the house and prevent the windows from fogging? Is it possible that the ventilation system is still not correctly adjusted? How can something like this be tested?
Information about the picture:
- Bedroom (16 m² (172 sq ft))
- Room temperature approx. 18-19°C (64-66°F)
- Two adults and occasionally a toddler (2.5 years)
- 1x supply air (Zehnder)
Thank you very much!
Bastian
We are using a Zehnder ComfoAir Q350. Unfortunately, it has had some issues with the "installation" from the start. First, the wrong settings were applied, and then the interior doors were too airtight. After the ventilation technician visited about five times since summer, it is now running reasonably well. Although the air quality in the bedroom still feels as if we have no ventilation, according to the technician everything is set up correctly.
Now that the weather has turned quite cold recently, we have noticed significant condensation on the windows in some areas. Especially in the bedroom and also in the open living-dining area. The technician said this is normal in a new building – however, due to the ventilation system and underfloor heating, we only have about 25% humidity. With an additional humidifier (Venta), we manage to reach almost 40%.
Question: Shouldn’t a ventilation system automatically remove moisture inside the house and prevent the windows from fogging? Is it possible that the ventilation system is still not correctly adjusted? How can something like this be tested?
Information about the picture:
- Bedroom (16 m² (172 sq ft))
- Room temperature approx. 18-19°C (64-66°F)
- Two adults and occasionally a toddler (2.5 years)
- 1x supply air (Zehnder)
Thank you very much!
Bastian
B
baschdieh22 Jan 2019 11:50Lumpi_LE schrieb:
Regardless of how well or poorly the ventilation system works, the windows should not be fogging up like this. The windows are soaking wet, with an average indoor humidity of 30% and temperatures of 18-19°C (64-66°F).. this is unacceptable.Okay – what can I do? Should I have the windows inspected again?
Measure the surface temperature of the glass using a suitable thermometer.
In theory, with 35% relative humidity and 19°C (66°F), dew point should occur around 4–5°C (39–41°F). However, the windows should have a temperature closer to 15–16°C (59–61°F).
Your issue can basically only occur with intact double-glazed windows and around 65% relative humidity.
In theory, with 35% relative humidity and 19°C (66°F), dew point should occur around 4–5°C (39–41°F). However, the windows should have a temperature closer to 15–16°C (59–61°F).
Your issue can basically only occur with intact double-glazed windows and around 65% relative humidity.
B
baschdieh22 Jan 2019 13:17halmi schrieb:
Looking at the values, I can't imagine the ventilation system is operating correctly. Ultimately, there is no improvement in indoor air quality; it only becomes acceptable when the windows are opened. I would focus on that issue first.
Is it double glazing? Thank you for your message. Yes, the panes are double glazed.
halmi schrieb:
Looking at the values, I can’t imagine the ventilation system is working properly.You can’t really conclude that from the values.
The development of the CO2 concentration is quite normal for a properly designed mechanical ventilation system with heat recovery for a single-family house. I would also consider it a bit high, but it is unrelated to the issues.
Similar topics