Geothermal heat pump / underfloor heating

Hello everyone, I have a question. Over the weekend, we looked at a single-family house that was built in 2004. It has a geothermal heat pump on the ground floor, underfloor heating, and "normal" radiators on the 1st floor. We took the time to look into the heating system and came across the fact that using "normal" radiators is not optimal for the geothermal heat pump. Does anyone of you have experience with this? If the setup is very disadvantageous, the question arises whether retrofitting is possible without problems and what it would approximately cost for about 65 sqm? Best regards, Jenny

Heat pumps require low flow temperatures to operate as efficiently as possible. Surface heating systems are very suitable for this, but there are also low-temperature radiators. Retrofitting water-based underfloor heating is almost equivalent to a major renovation - that is nonsense. Ultimately, you don't have to care. Just have the consumption costs documented and decide whether that is acceptable to you.

Thank you for your response. So the consumption costs are 800 euros per year. That is not much in our eyes, but according to the owners' statement, they don't need it warm on the upper floor. In the bathroom, I would like it to be warm in the morning before getting into the shower. :)