ᐅ Controlled ventilation system + fireplace + kitchen exhaust – does this work?

Dogma schrieb:

But in principle, you need to make sure that no negative pressure is created inside the house,

That’s what our general contractor also told us, and then referred us to the chimney sweep.

Nice-Nofret schrieb:

For example, our fireplace has its own air supply and is independent of the room air.

So, in the case of a room air-independent fireplace, would the controlled ventilation system experience no restrictions (like having to turn off, etc.)?

hampshire schrieb:

Get the combustion air for the fireplace from outside.

Should I have the combustion air “planned in,” or what exactly does that mean? Because we don’t want that back and forth of turning something on while turning something else off!

nordanney schrieb:

Still had to have a differential pressure monitor installed.

A differential pressure monitor—does that mean it tells you when to let air in, or what exactly is its purpose?

Yaso2.0 schrieb:

So, with a room-air-independent fireplace, would the mechanical ventilation with heat recovery have no restrictions (like being turned off, etc.)?

It depends on the mechanical ventilation system and the chimney specialist. So, the answer is a clear maybe.
In our case, the room-air-independent fireplace alone was not enough.

Yaso2.0 schrieb:

Should I have the fresh air supply "planned in," or what exactly does that mean? Because we definitely don’t want a back-and-forth situation, turning one thing on and another off, etc.!

Exactly, the fresh air supply can be provided either through the chimney, an exterior wall, the basement, or beneath the floor slab.

Yaso2.0 schrieb:

What does the differential pressure monitor do? Does it tell me when I need to let in air?

A differential pressure monitor is connected, for example, to the mechanical ventilation system. As soon as a certain negative pressure develops in the living room (which could theoretically cause combustion gases to be drawn from the fire), it will, for instance, shut off the mechanical ventilation system (although this requires a connection to the ventilation system, either directly or via switchable power supply). With an extractor hood, this also needs to be integrated, for example, through window contacts (or the differential pressure monitor switches off the mechanical ventilation every time you turn on the hood). Recirculation mode, of course, poses no problem.

Your first contact should actually be the chimney specialist. Ideally, you should know which mechanical ventilation system you will install and what type of fireplace you plan.

nordanney schrieb:

It depends on the mechanical ventilation with heat recovery system and the chimney technician.

Ok, then I will contact him; we still have the same one here 😀

nordanney schrieb:

Exactly, either through the chimney, through the exterior wall, the basement, or under the slab.

There is no basement. But I will consider what makes the most sense for us!

nordanney schrieb:

A differential pressure monitor is connected, for example, to the mechanical ventilation with heat recovery system. As soon as there is a certain negative pressure in the living room (which theoretically could draw exhaust gases from the combustion appliance), it will, for example, simply switch off the mechanical ventilation with heat recovery system (this requires a connection to the mechanical ventilation system, either directly or via a switchable power supply). For an exhaust hood, this also needs to be integrated, for example, via window switches (or the differential pressure monitor switches off the mechanical ventilation system every time you turn on the hood). Recirculation mode of course works without any issues.

In fact, your first contact should be the chimney technician. Ideally, you already know which mechanical ventilation system you will get and which combustion appliance you are planning.

At the moment, I know that the mechanical ventilation with heat recovery system will be a Vaillant recoVair, but there are probably many different models. We would like a panoramic fireplace again, which will be operated with firewood/wood briquettes.

A stupid question, which might have been discussed several times already… But is a mechanical ventilation with heat recovery system enough to remove cooking odors more quickly from the house, so that an exhaust system might not even be necessary?

Yaso2.0 schrieb:


A silly question, which might have been discussed several times already.. But is a mechanical ventilation system enough to remove cooking odors from the house quickly, so that an exhaust hood might not even be necessary?

We have the setup of an airtight fireplace, a ventilation system, and a recirculating range hood.

You can get rid of the odors, but it will take noticeably longer.

I have linked our ventilation system with the range hood. When the range hood is turned on, the ventilation system runs at its highest setting and continues for 15 minutes after the hood is switched off, then returns to automatic mode.

gmt94 schrieb:

We have the setup of a room-air-independent fireplace, a ventilation system, and a recirculation hood.

You will get rid of the odors, but it will take significantly longer.

I have linked our ventilation system to the cooking hood. When the hood is on, the ventilation system runs at its highest setting and continues running for 15 minutes after turning off, then returns to automatic mode.

Is this done purely through conventional electronic wiring, or do you need KNX or something similar for this?

My Buderus system has two potential relay contacts. Using the configuration tool, you can assign different functions to each relay.

I don’t have a KNX setup at home, so I solved it with two Shelly devices.

A Shelly Plug S is connected behind the range hood. It’s a simple adapter that plugs into the power outlet and can measure electrical power consumption.

The ventilation system is connected to a Shelly 1. This one has a potential-free relay, which acts as the relay contact.

Everything is integrated on a Raspberry Pi running Homematic, where the control logic takes place.

It is also possible to control the whole system via the Shelly app using scenes, but I believe that requires cloud access. However, I’m not entirely sure because I don’t use that option.

There are certainly similar KNX components that can achieve this as well.