Hello,
That is not surprising at all. If you asked more questions, X new variants would appear and the confusion would be complete! The ultimate and universally valid heating system definitely does not exist! However, there is a particularly advantageous solution for every project. This must be found. The building, orientation, location, climate site, user behavior, etc. form a unit. Also, the building services engineering (heating, hot water preparation, ventilation, etc.) must always be considered as a whole. Without knowledge of your individual boundary conditions, no objective recommendation can be given if it is to be sensible and effective.
The groundwater level alone is by no means a decision criterion for a groundwater heat pump! Due to the requirements on water quality, there are relatively few sites that would be suitable for the effective use of a groundwater heat pump! Here too, the boundary conditions must first be clarified (recharge, abstraction wells; iron ochre formation). If the periphery is right, very good annual performance factors are achieved.
That can be a possibility, but it is not said that this is actually the cheapest option for you. Most often, estimates and assumptions are made here, not calculations, which prove very disadvantageous in later operation.
The above said also applies here: first, the framework conditions must be clarified! Air heat pumps have characteristic curves that most strongly oppose the actual demand (building curve)! Therefore, they are predominantly used bivalently, i.e., with an additional heating rod at low outdoor temperatures. That means partial electric heating! Otherwise, they would be mercilessly oversized during main operation, which can lead to significant problems. In addition, another component, ventilation, is involved here, making a real comparison practically impossible! It should be clarified in advance whether a ventilation system is even required/necessary, or desired for comfort reasons! In heat recovery, efficiencies are mostly advertised that are hardly ever reached in practical operation. Therefore, this investment should also be carefully reviewed in advance. Nevertheless, despite their lower annual performance factor compared to other heat pumps, air heat pumps can represent a good solution in individual cases, provided sufficient dimensioning! Here, the energy demand for hot water preparation has a particularly large influence.
Where does the insurance advisor get his knowledge from? He certainly has no training in technical building equipment! You don’t go to the baker for toothache!!!
Again, basic and sweeping. Both underfloor heating and radiators or convectors each have their pros and cons. Underfloor heating and hot water heating are sluggish, therefore heating on demand is hardly possible; i.e., continuous heating is usually necessary! The fireplace will primarily be responsible for the "fire" experience! Sustainable savings effects in connection with underfloor heating will hardly be possible, as it cannot respond adequately to the additional heat source. Radiators are much better suited for this purpose. Their quick regulation behavior allows heating "ad libitum." External heat sources (fireplace) can be used much more efficiently. Depending on user behavior and building insulation standard, this can achieve significant savings effects without loss of comfort. However, with increasingly well-insulated building envelopes, these savings become smaller, so the difference hardly remains effective. The limit can be calculated in advance. With heat pumps as heat generators, however, underfloor heating is a prerequisite for effective operation. Warm feet in the bathroom are no longer reasonably possible. Additional heating surfaces are often required.
Basically: Before signing a contract, a sufficient check and calculation must be carried out. This includes in particular the heat load (DIN 12831) as well as the annual energy demand for heating and hot water! Based on this, the overall concept is developed. The results from the Energy Saving Ordinance verification are generally not suitable for this!!! Objective and independent advice is only obtained from a qualified expert who does not sell, install, or broker!
Best regards