Experience, running costs Rotex HPSU Comptact 308

Hello everyone,
I have an offer from the developer (Heinz von Heiden) for my planned house (Arcus 160 - 152.57 sqm (according to WoFIV) and 164.79 (according to DIN 277).
It is a combined unit (water tank and indoor unit combined)
According to the offer, the device is designed for 170m2.

- What are your opinions?
- My buddy says that the indoor unit will need to be repaired/maintained again. If it is combined with the water tank --> difficult
- What has been your experience with the device so far?
THANK YOU for your response.

Throw the offer away... Anyone who designs a heating system based on m2 of living/heating area deserves to be shot. That’s just simple sales talk or sales calculation. For example, 170 m2 of living space on the Zugspitze, in Cologne, in Alaska or in the Congo—does this heat pump suffice to warm the house everywhere? Insist on designing the heat pump based on a proper heating load calculation and underfloor heating design. And don’t let the thing be oversized.

We have had such a system from Heinz von Heiden in operation for 5 months now, including cooling function.

It does first of all what it is supposed to do. It would be bad if it didn't. I can't really say more about it yet – neither positive nor negative.

Regarding the design of such a heating system: I think the reference to the living area is more understandable for the average consumer than heating load. And it will probably cover 85..90% of the cases, especially when preparing an offer. For the building application or the energy certificate, a detailed calculation must be available anyway!??

There is a database for real consumption of heat pumps, similar to Spritmonitor, which can be found via your search engine. The significance is limited to the respective conditions but serves as a reference point.

The heat pump should not be oversized and the surface heating optimized for the lowest possible supply temperatures. For this, the room-by-room heating load calculation is used. Ideally, you also specify your own desired temperatures there (24° according to DIN necessary in the bathroom?). Ask early for this calculation and for the calculated maximum supply temperature, then you know where you stand. More than 35° is not permitted in new buildings; up to 30° should be aimed for. Do without buffer storage and individual room control. You can find a lot of information on all these topics on the internet from other builders.

Für den Bauantrag bzw. den energetischen Nachweis muss doch eh eine detaillierte Berechnung vorliegen!??

No, the proofs have little to nothing to do with the concrete planning of the heating system, is right about that. The construction companies make it easy on themselves at the expense of the builders and estimate wildly. Better a bit more so that the builder never freezes.

Just for your information. From January 2020, ROTEX will become: Daikin.
It seems Rotex had a trademark dispute with Daikin?!