The well that you drill will last a 100 years if you don't have bad luck. That is half the cost of installation.
The water/water heatpump unit in my house is 20 years old and has not had any major failures yet. I hope it will run for another ten years before the compressor gives up, but it is indeed approaching its calculated technical lifespan. I estimate it will set me back €10k to have it replaced.
Air/air is the cheaper option over time, even in most of Scandinavia with coldish winters. The main drawback of air/air systems are that they are loud and ugly and therefore annoy both yourself and your neighbours.
The water/water heatpump unit in my house is 20 years old and has not had any major failures yet. I hope it will run for another ten years before the compressor gives up, but it is indeed approaching its calculated technical lifespan. I estimate it will set me back €10k to have it replaced.
Air/air is the cheaper option over time, even in most of Scandinavia with coldish winters. The main drawback of air/air systems are that they are loud and ugly and therefore annoy both yourself and your neighbours.