What are the legal requirements for a utility room with an air-water heat pump?

Good morning,

a BU told me that a utility room must always have a window, regardless of whether there is a door or not.

What is the legal framework.

Thank you very much
Michael

A ventilation must be present.

It does not necessarily have to be a window.

There must be ventilation.

It does not necessarily have to be a window.

This is not meant to be provocative, but is that stated anywhere? It’s not too late yet for our utility room (without a window).

Controlled residential ventilation with extraction in the utility room is present, supply air accordingly through the door threshold, so formally that would certainly be okay, but in the event of a power outage, for example, you cannot manually provide ventilation.

We also have no window. It is wedged between the slope and the garage.
There is exhaust air via the [Kontrollierte-Wohnraumlüftung] like in Mottenhausen.

DIN 18 012

DIN 18 012

um, unfortunately I cannot find a single word about the ventilation of a HAR in DIN 18 012, did I overlook it? WHERE EXACTLY is it stated? under 5.5.2 House connection room 5.5.2.1 General there are various structural requirements, but nothing about ventilation. If instead of a room there is only a: 5.5.4 House connection niche there are specifications for the width of the door gap as ventilation. under 5.4.2 Gas it is also stated that the gas line supply must be ventilated: so the KG empty conduit must be ventilated using a T-piece, preferably directly outside the house. There is nothing more in DIN 18012:2018-04 on the subject of "(ventilation)". This should be the latest version, I cannot access a newer one via Perinorm.