Hello everyone,
we are building a KfW 40 house with a Viessmann Vitocal 200-S heat pump and an 8 kW photovoltaic system.
The heat pump is also capable of cooling. The upgrade would cost 1000 € (only the heating installer, thermostats extra).
Is it generally worthwhile to cool using the heat pump? Just because it can does not necessarily mean it is practical.
How fast does a room cool down? Underfloor heating systems are usually quite slow in response.
Or does it make more sense to invest in an air conditioning system and operate it with the photovoltaic system on hot days?
Thanks and best regards
Markus254
we are building a KfW 40 house with a Viessmann Vitocal 200-S heat pump and an 8 kW photovoltaic system.
The heat pump is also capable of cooling. The upgrade would cost 1000 € (only the heating installer, thermostats extra).
Is it generally worthwhile to cool using the heat pump? Just because it can does not necessarily mean it is practical.
How fast does a room cool down? Underfloor heating systems are usually quite slow in response.
Or does it make more sense to invest in an air conditioning system and operate it with the photovoltaic system on hot days?
Thanks and best regards
Markus254
Traumfaenger schrieb:
what would be a realistic indoor temperature for you in a KFW 40/55 house after two weeks of a heatwave? 😉According to various reports during heatwaves, peak temperatures of 28-29°C (82-84°F) are measured in the attic of solidly built KFW55 houses.
There are also some cases where these temperatures are not reached during heatwaves, for example when there is no south-facing roof window, etc.
R
RotorMotor17 Aug 2021 09:09Traumfaenger schrieb:
Cooling through underfloor heating by 2-3 degrees costs around 2,000-3,000 EUR (in one post even 4,000 EUR), while an air conditioning system costs over 13,000-16,000 EUR. If you feel comfortable with an indoor temperature of 33-35 degrees, then the 2-3 thousand EUR option is sufficient. However, if you prefer 21-24 degrees, you have to invest a five-figure amount for cooling a single-family house. There seems to be a major misunderstanding here again. The 2-3 degrees obviously do not refer to the outdoor temperature but to the indoor temperature you would have without any cooling.
With 30 degrees outside, the indoor temperature without cooling is not 30 degrees but depending on shading 23-26.
With underfloor heating cooling, it is then 22-23. I find that very comfortable!
Traumfaenger schrieb:
What would be a realistic indoor temperature for a KFW 40/55 house after a two-week heatwave for you? 😉Somewhere in the low 20s Celsius (low 70s Fahrenheit). If it were as hot as the temperatures you mentioned, I would sue the construction company and have them demolish the house at their expense.S
Stefan00117 Aug 2021 13:30We are currently having an air conditioning system installed in the hallway on the upper floor for about 4.5k. However, we will also be able to cool using the underfloor heating system. Hopefully, I will be able to report on the results and effectiveness next year.
Stefan001 schrieb:
I hope to be able to report on the results and effects next year. The question beforehand is, what does it currently look like or compared to “without” – over the course of one summer.
With air conditioning/radiant floor heating-cooling, the results are clear.
S
Stefan00117 Aug 2021 14:31driver55 schrieb:
The question beforehand is how does it currently compare to “without” during a summer.
With air conditioning / underfloor heating cooling, the results are clear.I actually plan to turn on the cooling only when it gets too warm for me. So I should be able to assess the difference between before and after. (Hopefully there will be a reasonably stable weather situation at some point)Similar topics