Hello everyone,
there is a topic that’s been on my mind. I only have some theoretical knowledge and don’t fully understand it yet, so I wanted to ask you. Maybe I’m already on the right track, but I’m not completely sure.
If I build a KfW 40 house and install a heat pump, I usually have underfloor heating.
The heat pump will probably heat the heating circuit based on demand. Do I also have a buffer tank here, or is it basically just the water in the heating circuit?
How does hot water generation work with a heat pump?
Is it common to have, let’s say, a 120-liter (32-gallon) hot water storage tank that is heated? Is this usually included with the system, or do I need an external buffer tank?
Or is it done without a large intermediate buffer, with the heat generated “online”? I suspect this might not work well since the heat pump is not usually sized that large.
Can the heat pump handle this in winter at all, or is it necessary to have an electric heating element switched on? The hot water should be heated to about 45°C (113°F), and in winter we can have temperatures down to around -15°C (5°F), so that would be a temperature difference of 60°C (108°F). I imagine that puts a lot of strain on the system.
Maybe you can help explain this a bit. Despite having quite a bit of knowledge about house building and heating, this part isn’t entirely clear to me yet. But maybe I’m already more or less right.
Thanks for your experience and knowledge.
Best regards,
Specki
there is a topic that’s been on my mind. I only have some theoretical knowledge and don’t fully understand it yet, so I wanted to ask you. Maybe I’m already on the right track, but I’m not completely sure.
If I build a KfW 40 house and install a heat pump, I usually have underfloor heating.
The heat pump will probably heat the heating circuit based on demand. Do I also have a buffer tank here, or is it basically just the water in the heating circuit?
How does hot water generation work with a heat pump?
Is it common to have, let’s say, a 120-liter (32-gallon) hot water storage tank that is heated? Is this usually included with the system, or do I need an external buffer tank?
Or is it done without a large intermediate buffer, with the heat generated “online”? I suspect this might not work well since the heat pump is not usually sized that large.
Can the heat pump handle this in winter at all, or is it necessary to have an electric heating element switched on? The hot water should be heated to about 45°C (113°F), and in winter we can have temperatures down to around -15°C (5°F), so that would be a temperature difference of 60°C (108°F). I imagine that puts a lot of strain on the system.
Maybe you can help explain this a bit. Despite having quite a bit of knowledge about house building and heating, this part isn’t entirely clear to me yet. But maybe I’m already more or less right.
Thanks for your experience and knowledge.
Best regards,
Specki
Specki schrieb:
Photovoltaics will definitely be installed on the roof anyway. It will probably be a KfW40+ house since, as you mentioned, the battery storage is practically free with the additional 5,000 euros. So, the storage can be kept as small as possible. They’re just not economical yet... I’m currently installing a 24.5 kWp system on my existing house, but without storage.
A hygienic storage tank is clear, but what does “Stumpf” mean?
a) There are rules about how large the storage must be. Your solar installer should be able to tell you.
b) It’s a metal container with 200 liters (53 gallons) of warm water inside :P
We have 350 liters (92 gallons) of hot water, but three people, a rental unit, and a rain shower. I’m not worried about legionella.
Hello,
I’m jumping in here.
We are five people, and I like to take long showers—sometimes 15 to 20 minutes. Therefore, we need quite a lot of water, but there is very little space available in the utility room.
According to the building contract, a heat pump from Rotex, model HPSU Compact, or Vaillant, model flexo Compact, is planned. The installer offered to install a Weishaupt WWP LS 8-B R-E at the same cost.
I compared the storage tank volumes:
HPSU Compact: 300 liters (79 gallons)
flexo Compact: 171 liters (45 gallons)
Weishaupt: 165 liters (44 gallons)
Even though the HPSU probably doesn’t have the best energy efficiency and also uses hot water for defrosting, it still provides the most hot water. Or am I missing something?
Which other compact units from different manufacturers also have a large integrated storage tank? What other alternatives do you see?
Best regards,
Simon
I’m jumping in here.
We are five people, and I like to take long showers—sometimes 15 to 20 minutes. Therefore, we need quite a lot of water, but there is very little space available in the utility room.
According to the building contract, a heat pump from Rotex, model HPSU Compact, or Vaillant, model flexo Compact, is planned. The installer offered to install a Weishaupt WWP LS 8-B R-E at the same cost.
I compared the storage tank volumes:
HPSU Compact: 300 liters (79 gallons)
flexo Compact: 171 liters (45 gallons)
Weishaupt: 165 liters (44 gallons)
Even though the HPSU probably doesn’t have the best energy efficiency and also uses hot water for defrosting, it still provides the most hot water. Or am I missing something?
Which other compact units from different manufacturers also have a large integrated storage tank? What other alternatives do you see?
Best regards,
Simon
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