Junkers Geothermal Heat Pump STM-100 Experiences

....What exactly should I ask for or which documents should I request?

Normally, every construction contract is preceded by a basic assessment. This means: determining the actual demand for heating, hot water, and, if applicable, ventilation based on the targeted building structure, climatic location, and user behavior. Depending on the results and conditions, the respective overall concept is derived. Necessary calculation documents would include: standard heating load, room heating loads, heating surfaces, hydraulics. For controlled residential ventilation, of course, the consideration of required air volumes according to the air volume plan according to 1946-6.

....And does our developer or general contractor have to provide us with something like this, or do I as the client have any leverage to make demands?

Usually not, because their contractual conditions generally do not provide for this. Only the contractual components apply, provided the contract has already been signed. It is usually the case that one has to live with what is given in the long term. In fact, this is economically viable in very rare cases. It is not for nothing that many general contractors/general entrepreneurs exclude these trades from the general contractor/general entrepreneur contract from the outset and award these services externally

v.g.

To come back to the topic of the buffer tank once again.

How can it be avoided? Is this basically possible with the planned Junkers compact system as well?
Besides lower efficiency, the space requirement for the buffer tank also annoys me.

To come back to the topic of the buffer tank. How can it be avoided? Is this basically also possible with the planned Junkers compact system?

Compact systems are usually a cheap compromise from the provider! If heat generation and demand match, a buffer tank (heating operation) in conjunction with a brine heat pump should definitely be avoided. Besides the space requirement and efficiency reduction, the unnecessary additional investment is more than dispensable!

Best regards