Air heat pump or use gas and solar?

A slap in the face for anyone who would have to pay an additional 10k or more [emoji23] From my point of view, a drastic wrong decision given the framework conditions, but you have to feel comfortable and trust your system technology, not me [emoji4] I'm curious to see how it will go on.

I see it exactly the same way. He would simply get "10 - 15,000 euros gifted" and then he decides against it. You can do that, but you don't have to understand it.

What kind of heating are you going with now?

I am installing a Viessmann Vitodens-300W and a Vitosol 200F solar module.

Why 10,000 to 15,000 given away? I doubt that even 5,000 euros will pay off.

That seems to be a huge matter of belief. As I said, experts also give advice in both directions. A few even say that it is balanced and basically you can't go wrong with either.

I'll put it this way... With a conventional/proven oil or gas condensing boiler, there is a much higher chance that the heating engineer installs, plans, and adjusts it well. Unfortunately, a lot of botched work is done with heat pumps. A heat pump—whether air, ground, or water source—is a sensitive subject. There is a lot to coordinate and plan. And often it fails at the planning stage. (Although, based on the prices asked by heating engineers, you might think you're buying a coordinated system.)

Thus, the oil and gas solutions run more reliably and better than many heat pumps.

The Energy Saving Ordinance also does its part when individual room controllers are prescribed even for heat pumps. From a hydraulic perspective, this is an efficiency killer for the necessary minimum flow rate of the heat pump. The nice manufacturer will say, that’s what our buffer tank is for. Also demonstrably reducing efficiency.

(P.s. one could get exempted from the individual room controllers... but who actually does that in practice?)

Well, there is nothing economically better than a gas heating system, but unfortunately there is no gas supplier in rural areas. And liquefied gas is simply more expensive and with a tank not such a great alternative.

I received feedback today. If they install towards southeast, they can only install three instead of the previously offered four flat collectors with 10m² (flat) due to the chimney. This reduces the price by € 890.00.

Apparently, this is then legally not a problem. It can probably be commissioned that way.

I have seen that there is an official penalty catalog for violations of the Energy Saving Ordinance. It also states that the builder is always primarily responsible for violations.

So, do we not have to worry if the contractor

a) uses fewer flat collectors than calculated (because on the east side we chose, there is not enough space due to the chimney)

b) places the collectors flat at 15°, which was not initially planned.

I have read that compliance with the Energy Saving Ordinance is also monitored by the authorities, and I do not want to get into trouble later. Is it 100% certain that we will not have any problems with our approach?