ᐅ Adjustment of the Ventilation System – Special Case

Created on: 7 Nov 2019 13:40
B
BBaumeister
Hello, I hope you can help me with the following question.
We live in a detached single-family house built in 2018, meeting the KFW 55 standard, with walls made of filled brick. The house has a volume of almost 1000 cm3 (61 cubic inches).
We have a Wolf CWL 400 ventilation system. At the moment, only two of us live here (children are planned). We both work full time and leave the house at 7:00 AM and return around 6:00 PM on weekdays. Now we are wondering what the required air exchange rate should be and how to best set the ventilation system so that we need as little heating as possible in winter while still having clean air.

At night, the system runs at 130 m3 per hour (4600 cubic feet per hour), and during the day at 250 m3 per hour (8800 cubic feet per hour).
Basically, we want the bathroom and bedroom to be ventilated adequately. After showering, we ventilate the bathroom briefly anyway, but then wet towels still dry there.
Otherwise, we spend a short time in the kitchen and living room in the morning for breakfast and about three hours in the evening. In my opinion, the ventilation is set too high for this situation.

It looks different on weekends. There, we cook extensively, have guests, do laundry, etc. Therefore, I would leave everything as it is on Saturdays and Sundays, but for the weekdays I would like to hear your opinion.
B
BBaumeister
8 Nov 2019 11:42
I reviewed the architect’s documents again. The total volume, including the basement, is actually 710 m3 (basement is also ventilated). The air quality is really excellent. Even cooking odors disappear after a very short time. I might lower the system a bit during the day and see what happens. Thank you very much for your help in any case.
Mycraft8 Nov 2019 12:06
Yes, go ahead. Feel free to experiment with it a bit.

So, approximately 180 m² (1,940 sq ft) of living space, I assume? (Without a basement).
I
Ippebson
8 Nov 2019 21:15
Where can I see the set airflow rate in m3/h (cubic meters per hour) on the system?
I have the Vallox MV 350, and as far as I can tell, only the fan power can be adjusted in percentage, separately for supply and exhaust air. I will take a picture of the interface menu when I get the chance.

Good luck
Mycraft8 Nov 2019 21:37
It varies with each system. In your case, you can adjust the fan capacity in percentage values.

Here you can see the values in m³/h (cubic meters per hour).


Two diagrams: Left shows power (W) vs air volume; Right shows pressure loss/air volume (supply air/exhaust air).
I
Ippebson
8 Nov 2019 22:19
Question marks over my head...