Does the exhaust duct of the fresh air system need an exhaust cover in the air duct of the bathroom?

It should be that the flue of the whole unit is not clear (or someone has changed the flue due to home renovation), and you should find the property to check it. There is also a method, that is, without the flue (sealed), directly discharge the air duct of the range hood to the outside.

It can be changed, but I don't know if the acceptance can be passed, and whether the deposit can be returned. Generally speaking, the design of these shared pipes has its own basis, if it is smaller, I am afraid that there will be other problems, so please consider it.

There are regulations for the exhaust pipes in the bathroom and kitchen, and they are not ordinary pipes. You're changing the design of your house without permission.

It's generally fine, it's an earthquake, and I'll talk about it if I survive.

There is no need to install, there is an exhaust air, the kitchen has a range hood, and the toilet has a bath bomb with exhaust.