ᐅ Ground slab penetration for heat pump outdoor unit

Of course, there are larger single- and multi-line entries as well, such as the Kraso KDS 150. You need to check whether the suitable system seals are actually available there for multiple pipes with standardized diameters (including insulation).

Normally, however, DN100 should be sufficient – most manufacturers offer sets in this size for split heat pumps. The brands mentioned above have an inner diameter of 100 mm (4 inches). 78 mm (3 inches) is the standard inner diameter for multi-line entries and is clearly too small for these purposes, unless you use more than one entry – but even then it’s rather tight. I had quite a hard time pushing my brine pipes (DA40, PE-100 RC pipe) through each standard multi-line entry – it worked in the end, but I wouldn’t want to do it again.

SaniererNRW123 schrieb:

Question: Does it really have to go through the floor slab? Where is the heat pump located? If it is "just" in front of the utility room (on the ground floor), you can simply go through the wall. The route should always be as short as possible.

Firstly, that, and secondly also cheaper to purchase.

Okay, thanks for the additional information.
The problem is that the pipes would cross a path between the yard and the main entrance.
If we eliminate this path, routing through the wall would be a solution.

However, you would then always have to walk around the front garden to get from the yard to the entrance.

The multi-conduit system is actually intended for utility providers (water, electricity, telephone, gas (?)) and is sometimes mandatory for them.
For the heat pump, the mentioned PVC sewer pipe is basically sufficient, which is installed directly near the heat pump inside the house.
What’s the problem? Properly sealed like all other PVC sewer pipes in the foundation slab, no moisture or pests can enter...
Similarly, additional cables, for example for the garage or garden, are sometimes routed through it as well...!?

I had originally planned with the builder to run a drainage pipe through the foundation slab for the heat pump lines. However, my HVAC technician preferred to run them through the wall because the pipes are quite thick and rigid. Now I have both. So far, no mole has appeared in the utility room...

A sewer pipe can be easily sealed between concrete and pipe. Just like any other wastewater pipe.
According to standards, using a sewer pipe for pipes installed underground is not acceptable.
Whether this is actually a serious issue in practice, I cannot say.