ᐅ Central ventilation system Vallox 350SC

Hello everyone, we have a Vallox unit 350 SC. I have a few questions about the settings. Unfortunately, the hotline couldn't help me. Even consulting the field service technician didn’t lead to any answers. Apparently, this person knows even less about the device than I do.

Does anyone here have a Vallox unit and can tell me if it has a bypass installed and whether it operates automatically? When I access the device, I can see at the bottom that I can turn the bypass on and off. It is currently set to on. What puzzles me, however, is the following: Looking at the supply air, room air, and exhaust air, I assume the bypass is not working. When we had 33°C (91°F) outside, temperatures of 27°C (81°F) were being delivered into the house during the day. Is this a result of the bypass reducing the temperature from 33 to 27 degrees? Or is this simply due to normal heat recovery?

Also, what does the 15° (59°F) temperature setting mean for the different ventilation modes? The controller can be set anywhere from 5 to 25° (41 to 77°F). What effect does this have?

Does the (existing?) bypass need to be deactivated in winter? Thank you very much for your feedback.

The unit should have a bypass.
And it should also be automatically controlled.
That is what the temperature setting is for.

At a 15°C (59°F) setting, the device tries to reach 15°C (59°F).
That doesn’t sound very logical.

What exactly is your issue with the unit?

I am generally satisfied with the device. However, I didn’t know what the temperature setting actually does. So far, the supply air temperature has never even come close to the 15 degrees Celsius (59°F) range (which, as I have now learned, doesn’t really make sense). Even when the outside temperature was 0 degrees Celsius (32°F). Since it was the preset temperature, I left it as is but always wondered what effect it had.

I also asked here because I would like to reduce the amount of warm air being introduced during the height of summer and to find out what options are available. For example, turning it off during the day and using quick ventilation at night, or something similar.

Tx-25 schrieb:

I am basically satisfied with the unit. I just didn’t know what the temperature setting does. So far, the supply air temperature has never been anywhere near the 15°C (59°F) range (which, as I’ve now learned, isn’t really useful). Even with an outside temperature of 0°C (32°F).

Yes, at 0°C (32°F) (and even earlier) the bypass closes again to prevent condensation in the pipes.
So, there are only a few moments when it is active.

Tx-25 schrieb:

Since it was the preset temperature, I just left it but always wondered what it actually does.

That is the target value, which the system then tries to achieve while taking other parameters into account.

Tx-25 schrieb:

Also, I asked here because in midsummer, I would like to introduce less warm air and was wondering what options are available. For example, switching it off during the day and using cross-ventilation at night or something like that.

That is not necessary. During hot weather, the system runs through the heat exchanger. This means it also recovers “coolness” accordingly.

However, the effects are relatively small. Due to the low air volume, only minimal temperature changes are achieved.

We have a Vallox 350 MV. Ours has a bypass that it controls automatically. Is your unit connected to the network? I find that the web interface makes everything much easier to understand.

Please don’t take the room air temperature shown in the picture too seriously. The ventilation system is installed in the basement, which is part of the thermal envelope but does not have any ventilation or air conditioning itself. The air conditioning is currently running in the living areas. When you go down to the basement, it almost feels like you've changed continents.

Yes, I have this exact surface as well. What temperature setting do you use in ventilation mode? Was it preset to 15°C (59°F) for you too?
Unfortunately, I don’t have a network connection near the device, so I can only access the interface very poorly.