ᐅ 1 Year with the Ventilation System: Clarity, Facts, and Energy Costs

Created on: 27 Aug 2013 23:56
B
Bastelwastel
B
Bastelwastel
27 Aug 2013 23:56
Hello, this is my first post here in the forum,

this post is meant to provide practical facts for those who are still undecided!

We have been living in our new build for 2.5 years now, and since August of last year I have been diligently recording the gas meter readings and entering them into a spreadsheet. I compared the actual consumption values with the forecasted values from the energy certificate, resulting in a nice consumption statistic for the billing period 2012/2013.

About the house:

Single-family house, two stories, with 220 sqm (2370 sq ft) plus a full basement.
Basement: waterproof concrete, insulation?
Ground floor and first floor: cavity brickwork, insulation 0.35 from Knauf, 15 cm (6 inches) (the black one)
Windows: triple-glazed with external blinds, large window front facing southwest
Heating: underfloor heating, gas condensing boiler with solar hot water and heating support
Ventilation: Paul Novus 300 (with touchscreen display)

Back when planning, we had to insist quite strongly on the ventilation system since it was new territory even for our architect. And today I can say YES, the money was worth it.

In our energy certificate prepared by the structural engineer, the ventilation system was not included. We arrived at a value of 69 kWh/sqm per year (kWh/sqm a).

Now the E.On billing year has "finally" ended and I was able to do the evaluation.

Despite the rather long winter (in April and May we consumed much more than in the energy certificate forecast), we ended up with a consumption value of 56 kWh/sqm per year (kWh/sqm a). Since domestic hot water energy is included in this figure, the number of occupants is also important. We live in the house with two adults and two small children.

Because I installed two small electricity meters (about the size of a circuit breaker) during the electrical installation, I know exactly how much the ventilation system and how much the heating and solar system including all pumps etc. consumed.

Ventilation: 323 kWh
Heating: 383 kWh

Regarding ventilation in general: simply brilliant!

The Novus 300 at our place is set to the normal load of 60% and it runs every day. At night on level 1 (power 20%) and when necessary on level 3 (which I set to 100%).

The comfort gain is mainly noticeable in winter.
One example:

In the evening after showering or bathing, everything is wet. What do you do when you're done? Open the window and let in the -10°C (14°F) cold air or just tilt it and then forget to close it, and in the morning you freeze on the toilet seat and the radiator thermostat runs full power because of frost protection.
BUT! Not in our house, because we keep the windows closed and the ventilation system takes care of the rest (then on level 2). In the morning it's not musty and everything is dry.

Second example:
We have a utility room on the ground floor with an exhaust vent where we dry laundry, and this works very quickly thanks to the constant air exchange while the windows remain closed (great for anyone with pollen allergies).

What I have often heard is that some are afraid there might be drafts at the doors or whistling noises. We don’t have that problem, even at full power. For the glass doors, the frames were simply installed slightly higher to allow an air gap. The best way to demonstrate the airflow is with a lighter flame or standing barefoot directly at the bathroom door—that’s when you realize what’s happening.

One negative issue:
I made the supply and exhaust air ducts through the basement light wells to the outside ("special basement windows"). Normally no problem, but at the exhaust air shaft the air noise is clearly audible and that is also where the terrace is, which is a little annoying. But when we sit there in summer, we just turn the system off or set it to level 1.

I could list many more positive examples.

If anyone has questions, feel free to contact me! I’m happy if I can help.

P.S.: I am not a salesperson and have absolutely NOTHING to do with the mentioned companies!
€uro
28 Aug 2013 07:29
Hello,
Bastelwastel schrieb:
....We have been living in our new build for 2.5 years now, and since August last year I have been diligently reading the gas meter and recording it in a spreadsheet. I compared the actual consumption values with the predicted values from the energy certificate, ....Despite the rather long winter (in April and May we consumed much more than in the energy certificate forecast)...

How could it be any different? The energy saving regulation certificate is intended solely for primary energy comparison purposes and certainly not for assessing actual consumption. It is even prohibited to derive consumption forecasts from it.

Best regards
S
Steusel
16 Feb 2015 11:08
Hello,
since this thread is a bit older, I wanted to ask if anyone has more recent information on the current power consumption of a ventilation system?

We would like to build with a ventilation system, but there is little information available online about the additional running costs.

Thanks for the responses.....
Y
ypg
16 Feb 2015 12:05
Hello Steusel,

Although we have been living in our house with a ventilation system for a year now, we do not have a separate electricity meter.
However, our electricity consumption is not significantly higher than it was in our previous, older house.
I think this is balanced out by some household appliances being replaced, while the outdoor lighting stays on all the time.
Since there are only two of us, the electricity consumption of this continuous setup should become comparatively lower per person if more people live in the house.

Best regards,
Yvonne
S
Steusel
16 Feb 2015 12:20
Hello Yvonne,
thank you for your feedback. Could you please let me know what your consumption is?
We are also two people...

For the information of everyone else: We are getting a ventilation system from the company Zehnder, model 350R.
Y
ypg
16 Feb 2015 13:08
We have consumed just under 2700 kWh within one year.
Our heating system and controlled mechanical ventilation are from Wolf; we are very satisfied with Wolf. Our house is about 135 m² (1450 sq ft).