Air heat pump and electricity consumption

Hello,

I don’t have one myself, but what can be gleaned from many problem cases in relevant forums is that the house should be at least KFW55 or better so that this system works satisfactorily and cost-effectively...

But certainly better than KFW 55 if there are not to be long faces afterwards

A conversation with an energy consultant will provide good insight here, because it is not the case that the frequently cited competitor with standard KfW 55 always and easily gets this status certified using exhaust air heat pump systems.

Rhenish greetings

Hello,

First of all, the basic question is which technology you want: oil, gas, heat pump. Then what type of heat pump: whether air/ground/deep etc. If you then choose air, there are probably again cheap stuff, standard and luxury variants, but all of which would fit the heat load calculation. Surely there is not just one manufacturer and one model.

I have gained the experience that homeowners always behave like a lid to a pot towards their provider. So whoever would basically choose the cheap variant and is also resistant to advice will get exactly what they deserve. Therefore, in my view, it is only fair & just that there are providers who specialize in this type of homeowner.

Finding the right one is certainly not easy.

But basically, yes. The first decision should be quite easy:

Are you more the type who sticks to what has proven itself — then decide on gas. This does not restrict you in any way, because if the first boiler gives up the ghost, you can always switch to newer technology. Since the newer generation of gas condensing boilers, the consumption costs are similar to an air-water heat pump; of course always depending on the heating and showering behavior of the house residents.

If you are willing to let go of old habits, then you should decide on a heat pump. Whether it is then an air-water heat pump, an air-air heat pump or a geothermal heat pump depends on the efficiency status of the new building as well as the property conditions and of course the budget.

One more thing — if you choose reputable providers and not the cheap ones, you will not be offered cheap technology either. Across gas, for example, Stiebel, Vaillant, Buderus and many other well-known manufacturers offer good devices suitable for the heat load calculation.

Rhenish greetings

I want reliable technology, so no cheap crap, but on the other hand, I don’t want to overpay for technology just because of a name.

To put it in terms of cars: for me, Skoda Octavia, VW Passat, and Audi A4 are roughly equivalent in terms of technology, safety, consumption, and space. My choice would be the Passat or the Octavia because I don’t see why I should pay an extra 2000 EUR per Audi ring.

What I want, probably like everyone with a limited budget, is a good price/performance ratio. In other words, the size of the living space in relation to the costs, as well as the heating technology in relation to the costs. This refers both to the acquisition and operating costs. The extra costs should pay off within the first 5–10 years; then I’m happy to invest more initially. But if it takes 20 or 30 years, it’s probably something for enthusiasts and idealists. By then, other technologies will be in use, before what is currently installed has even roughly paid for itself. For example, my father had very good experiences with gas boilers from Vaillant and didn’t even consider other heating methods. Now he’s dealing with heat pumps and also ventilation systems and seems to find it at least interesting and worth discussing.

By now, a ventilation system seems more important to me than the decision between air-water heat pump/gas, but now the preference for underfloor heating over radiators also comes into play, and whether that can be combined sensibly. Domestic hot water heating should be supported by solar, and a stove for transitional periods and cozy warmth is a must for us anyway.

I need to sort out all my thoughts and maybe describe the ideas combined. Complex topic... and I don’t want to talk myself into a corner. It certainly doesn’t have to be option x or y at all costs, because one is fundamentally great and the other is fundamentally nonsense. The combination of acquisition costs and everyday operating costs should be the cheapest for us and of course reliable at the same time.

Best regards

Hello, two aspects I can add: The whole calculation should also include the warranty periods and repair susceptibility of the individual systems. We decided on a heat pump for various reasons (not yet in use), but I am very skeptical whether it is financially worthwhile – because there are many moving parts, the warranty periods for the heat pumps are short (wonder why?) and repairs are expensive. The second aspect is maintenance costs. For gas, in my opinion, about 200 euros per year are incurred (may vary regionally). The heat pump is better here; it actually doesn't need maintenance. I've heard different stories—if you got a Monday pump, you just ended up holding the short straw. Advantage of the heat pump: No burner, so no ash and no carbon monoxide in the house.

Many moving parts in a heat pump? It’s just a compressor like in every refrigerator – those also last forever, despite continuous operation. It’s a technology that is almost 150 years old and proven. Therefore, no maintenance as you wrote. When I think about the costs for the constant repairs of our gas condensing boiler (from 2001), all the things that could have broken over the years...

: Really, several repairs even? The people with gas condensing boilers that I know, there has never been anything. Although one now had water in the chimney/flue (?), and somehow that caused the floors and walls in the basement to become damp and need drying. It's not the gas condensing boiler itself causing problems, I guess that can happen with any system with a chimney/flue(?) They should have had the chimney inspected regularly, which they didn't even know.
With the heat pump, there is at least the big rotor. For acquaintances, a temperature sensor was defective once, which was disproportionately expensive to replace, and apparently a lot had to be disassembled to get to it.