Lower indoor temperature after commissioning Controlled ventilation system with heat recovery

The effect probably does not come from the controlled residential ventilation but simply from the unheated rooms, which increase the heating load, and the heated rooms simply cannot maintain the temperature because they also have to "carry along" the unheated rooms.

I consider that very likely. Try to keep all rooms connected to the controlled residential ventilation at the same temperature.

If you don't want that, a decentralized ventilation would have been better.

Hi! I would also measure the temperatures.

For me, WRG is active and I have the following values...
Exhaust air inside: 20.7°C
Supply air inside: 17.4°C
at an outside temperature of 6.4°C

Daily course attached.

Yes, that is generally how it looks. The values are absolutely normal. Everything works here.

Ventilation means heat loss. Heat recovery reduces this well, better than window ventilation. But of course, heat is still lost. So you have to heat or otherwise ensure sufficient heat supply. With a new system, it is likely that it is not calibrated and tends to ventilate too strongly. Bypass check was already mentioned.

With us, heat recovery is also active, at 22.5 degrees exhaust air temperature and 19 degrees supply air temperature. Current outside temperature 2.5 degrees.

Best regards
Sabine

Do your controlled residential ventilation systems not have a preheater? If 2-degree cold air is blown into a room now, you can feel a draft.