ᐅ Alternative air-to-water heat pump to Weishaupt WBB 12-A RMD-AI?

Why are you looking for an alternative heat pump?
Who selected the heat pump? From my perspective, even with the limited information, I would say it is much too large.
What is the buffer tank for?

To provide a somewhat accurate assessment, answers to Daniel-Sp’s questions are needed.

If the information were available, I would share it. The additional floor construction will start no earlier than spring 2023. For this reason, there is so far only a detailed plan from the architect, and a heating specialist has reviewed it and proposed the Weishaupt heat pump. The buffer tank is used to store excess energy that is not immediately needed.

Since we are novices in this field, we are seeking a second opinion and therefore ask which manufacturer offers the best price-performance ratio. We cannot say whether the heat pump is possibly oversized; this is simply the result of the proposal. Thank you very much!

1. Without a heating load calculation, it is not possible to seriously recommend a heat pump.
2. How large should the heating buffer tank be for storing the heat then? 5000 liters (1320 gallons)?
3. Are you planning with underfloor heating or radiators?

Yes, with underfloor heating and no radiators. The offer includes: Weishaupt hot water storage tank WA300 and Weishaupt buffer tank WES200