Distribution system (supply air + exhaust air) in the upper floor floor

Hello everyone,

we have been offered the Reco Vair from Vaillant (GU: Town & Country).

The plan is for all supply air ducts to be installed in the floor of the upper floor. But all exhaust air ducts are also supposed to be installed in the floor of the upper floor. This means that all supply and exhaust air ducts are located in the ceiling on the ground floor and all supply and exhaust air ducts are located in the floor on the upper floor.

I have the following questions:

1. Let’s first consider only the supply air ducts on the upper floor. If all of these are located in the floor and the overflow occurs through a door gap below the room doors, will there, for example, be enough air exchange generated in the bedroom at all? Or does the supply air introduced at floor level flow directly to the door gap at floor level and into the next room without sufficiently ventilating the entire bedroom? Especially in the bedroom, the air in the upper room areas should also be exchanged! What do you think, will it still work?

2. Now about the exhaust air opening on the upper floor: This is located in the bathroom. I consider it insufficient if it is located only near the floor. After all, the water vapor should also be extracted and that is "near the ceiling." From my point of view, this opening must therefore be near the ceiling, or what do you think?

Then I have two more questions that have come up from other discussions, maybe you have answers for me? I would be very happy, anyway:

3. What should be installed, disk valves or covers?

4. How large should the nominal diameter of a supply or exhaust air pipe be so that we have no ventilation noises? (Our house has 180 m² of living space, distributed over ground floor / upper floor, ceiling height on the ground floor 260 cm and on the upper floor 280 cm. It is inhabited by 4 people)

5. What else do we have to consider so that we especially do not have disturbing noises? A quiet system with as little operating noise as possible is important to us. Does anyone know how loud the Vaillant Reco Vair is? Can you hear it in the hallway if it is housed in the house connection room adjacent to it and separated only by a normal door?

Or does the supply air introduced at the floor flow directly to the door slit at the floor and into the next room without sufficiently ventilating the entire bedroom?

At a constant flight altitude, the air would only flow if it were not warmed.

Especially in the bedroom, the air should also be exchanged in the upper room levels!

The exhaust gas from the breathing process is heavier and sinks within the ambient air. Since its concentration would otherwise increase, supply air during the night is sensible. Even technicians know a little about what they are doing ;-)

We have the supply air in the floor and the exhaust air in the upper part of the walls with diffusers on the upper floor. We were told that the supply air can be in the ceiling or in the floor, but the exhaust air should not be on the floor.

Best regards
Sabine

1. It absolutely does not matter where the valves are located, whether at the bottom, top, left, or right; as long as the valve is furthest from the door, mixing will take place. Additionally, the position of the elements on the outlet valves can be used to direct the flow pattern in the desired direction.

2. Just place them somewhere at half height near the pre-wall elements or cover shells; that is completely sufficient.

3. A matter of belief and optics... Function is given in both cases.

4. As large as it fits with the rest of the system, the room size, the desired result, and also the volume. This must be calculated, and there is no general statement.

5. Here too, the system must fit the house, meaning not too small and not too large...

Large means more space requirement, higher investment, etc., but lower speeds which inevitably become quieter.

Small usually means lower operating and acquisition costs but higher noise due to the higher speeds of the fans.

The diameters of the pipes and the use or omission of air distributors also play a role.

Type and construction of the silencers and so on...

Thank you very much for your answers,

so I will ask what exact components are installed and then put them here up for discussion again.

Overall, the topic of controlled residential ventilation is really a mystery to us.

The gain in comfort tempts us, but a system that we might be able to hear in the adjacent room would be an absolute no-go!

How is it with your systems, can you hear them through the closed door of the house connection room?

Maybe one of you also has the Vaillant Reco Vair?

That probably also depends on the door. Install a solid core door with a drop seal there. Interior wall nicely made of [Kalksandstein]. Then the chance of hearing nothing increases.