ᐅ Routing of Heat Pump Piping in New Construction – Challenges

Hello building services experts,

I need your advice on the pipe routing for my planned air-to-water heat pump.

Starting point:
The installation location of the heat pump is about 6 meters (20 feet) away from the utility room. The pipes have to pass through a bathroom.

Preferred monoblock heat pump:
The two water pipes currently have a diameter of about 10 cm (4 inches) each, including insulation. Ideally, I would like to lay them under the bathroom’s structural floor (floor construction: 18 cm (7 inches), of which 10 cm (4 inches) is insulation). My main concern is how to introduce these thick pipes cleanly and sealed from outside into the floor’s insulation layer without causing issues with the screed or needing to knock through the wall. In other words, how to pass through the wall deeply enough and sealed?
Alternatively, I could route the pipes through the 20 cm (8 inches) deep installation wall in front of the bathroom. However, this would require relocating the existing soil pipe (red dot in the drawing), which is feasible. Then the pipes would go left under the shower and into the floor.

Alternative split heat pump:
The refrigerant pipes here are significantly slimmer.
Idea: Could I lead the narrower pipes through the 20 cm (8 inches) deep installation wall, passing by the soil pipe and the WC element?

Running pipes under the slab directly to the utility room is something I would like to avoid due to cost and heat loss.

Are there any other, better ideas for the pipe routing that I haven’t considered yet?

Thanks for your feedback!

Hello,

Is this a new build? Then it should be under the slab.

Best regards

derdietmar schrieb:

Hello,

Is this a new build? Then below the slab.

Best regards

Yes, new build, but why does it have to be below the slab? What speaks against staying above ground? Apart from costs, I don’t see much heat loss over the long distance?

Run the pipes through the bathroom’s pre-wall, which is already fully planned, rather than through the floor.

wiltshire schrieb:

Run the pipes through the bathroom's pre-wall installation, which is already planned continuously, instead of under the floor.

The soil pipe is in the way here. With a diameter of 100mm (4 inches), there is very little space available. It might be possible to squeeze the pipes past it without insulation, but that seems a bit makeshift to me. However, I’m not a plumber.
Or would it be better to come in from the side behind the soil pipe through the wall in the garage driveway?

You only need 10 cm (4 inches) for heating pipes located outdoors. Inside the thermal envelope, half of that is sufficient, and sometimes no insulation is needed at all.