ᐅ Air Source Heat Pump and Electricity Consumption

Good evening,

willWohnen schrieb:

Although, one had water in the fireplace/chimney (?), and somehow this caused the floors and walls in the basement to become damp and needing drying. It is not the gas condensing boiler itself that is causing problems, I guess this can happen with any system using a fireplace/chimney(?). They should have had the chimney inspected regularly, which they didn’t even know.

This "would have" and "if" is always amusing...

This rather sounds like the acquaintance in question saved money on the required flue pipe for the gas condensing boiler in the chimney. Condensate forms with gas condensing boilers.

Regards, Bauexperte

sirhc schrieb:
I want reliable technology, so no cheap stuff, but at the same time I don’t want to overpay just for a brand name.

To use a car analogy: for me, a Skoda Octavia, VW Passat, and Audi A4 are roughly equivalent in terms of technology, safety, fuel consumption, and space. I would choose the Passat or the Octavia because I don’t see the point in paying an extra 2000 EUR (about 2200 USD) per Audi ring.

What I want, and probably everyone on a limited budget wants, is good value for money. That means comparing living space size in relation to cost, as well as heating technology in relation to cost. This includes both initial investment and operating costs. The additional expenses should pay off within the first 5 to 10 years; then I’m willing to invest more upfront. But if it takes 20 or 30 years, that’s more for enthusiasts and idealists. By then, other technologies will be available, even before what’s currently installed has amortized reasonably. For example, my father had great experiences with Vaillant gas boilers and didn’t consider other heating options initially. Now he’s looking into heat pumps and ventilation systems and finds them at least interesting and worth discussing.

Now, a ventilation system seems more important to me than choosing between an air-to-water heat pump or gas. But on top of that, I prefer underfloor heating over radiators and wonder if these can be sensibly combined. Domestic hot water heating should be supported by solar energy, and a stove for transitional periods and cozy warmth is essential for us anyway.

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

Best regards

If the additional costs are meant to pay off within the first 5 to 10 years, then from an economic perspective you shouldn’t buy a controlled mechanical ventilation system. And whether an air-to-water heat pump pays off in that time? Nobody knows—because nobody knows how gas and electricity prices will develop relative to each other.

And you can also forget about solar-supported domestic hot water heating. It’s not cost-effective and mainly serves to make the numbers look better for KFW (a German development bank subsidy program).

A stove for coziness means work, mess, chimney sweeps, chimney costs (even higher with controlled mechanical ventilation because it requires a room-air-independent system), firewood, etc.—and possibly an overheated living room. Experiences from friends and acquaintances speak volumes.

By the way, the car comparison is flawed. Take a look at older models: you’ll still find many good A4s, some good Passats, and fewer good Octavias.

Hello,

sirhc schrieb:

To put it in car terms: for me, the Skoda Octavia, VW Passat, and Audi A4 are roughly equivalent in technology, safety, fuel consumption, and space. My choice would be the Passat or the Octavia because I don’t see a reason to pay an extra 2,000 EUR per Audi ring.

I hope you don’t seriously believe—sticking to the car analogy—that a provider would “voluntarily” offer you an A4? With reputable companies, the offer will always be comparable mid-range models.

sirhc schrieb:

What I want, probably like anyone with a limited budget: a good value for money. That means looking at the size of the living area in relation to the costs, as well as the heating technology in relation to the costs. This applies both to initial investment and operating costs. The additional costs should pay off within the first 5-10 years; then I’m happy to invest more upfront.

There’s no all-in-one solution for you, either! I find the term “additional costs” confusing in the context of building a new single-family home. You will need heating technology, regardless, unless you are aiming for true passive house standards, which cost significantly more than your amortization calculations suggest.

A building services engineer (TGA planner) can help you most with this. However, since building services engineering is not yet widely applied in typical single-family homes, it tends to be disproportionately expensive—you should expect to pay between 2,000 and 3,500 EUR, depending on the scope of the commission. Unless, of course, you find someone like the unpopular planners here who undercut prices, but whether those calculations are reliable is anyone’s guess.

In the end, it comes down to trusting your own planner and heating load calculations or spending money to hire a TGA planner.

sirhc schrieb:

By now, a ventilation system seems more important to me than choosing between air-to-water heat pump or gas. Also, I prefer underfloor heating to radiators and wonder if it makes sense to combine them. Domestic hot water should be solar-assisted, and a stove for the transitional seasons and cozy warmth is a must for us.

I’m sorry to say this, but that is economically unsound. Visit a local energy agency and get advice. I’m confident that many of your assumptions will be reconsidered after that.

Regards, Bauexperte