Air conditioning: What is the royal way

What exactly do you want to know?
Our building is a new construction from 2013, 42.5 cm Poroton masonry with perlite filling, gable roof with 22° pitch, tiles and normal insulation between the rafters.

The heat pump is a Vaillant geotherm VWS 63/3 operated with two deep boreholes of 85m each. The extra cost for the version without cooling function was about €700, as mentioned. No other measures were taken.

The flow temperature on hot days is 20°C, I think 17-18°C should also not be a problem, but 20°C is completely sufficient for us.

On hot days we keep the shutters on the upper floor closed two-thirds, the blinds on the ground floor are in tilted position. The indoor temperature reached 24°C only once in the last weeks, 90% of the time it is below 23°C.

Ok, so you have a brine-water heat pump with two ground probes. I assume it also handles heating (underfloor) and hot water preparation completely for you. Or are there additional system components? Can you say something about the acquisition costs and operating costs?

Then you write that the controlled residential ventilation also cools in your case. Is an additional heat exchanger used there or is it connected to the brine-water system? What are the conditions for the controlled residential ventilation? What air temperature comes out? Acquisition costs? Running costs?

Honestly, your system would be my favorite if the cooling capacity is really sufficient. Otherwise, we are back to air conditioning, possibly combined with solar on the roof, which significantly reduces running costs.

Otherwise, you have shutters or blinds on all windows. What orientation does the house have? Many windows facing south, for example? Is there possibly natural shading? Large trees or shade from bigger buildings falling on the house? Do you have an attic directly under the roof and if yes, how are the temperatures there?

Oh yes, and how was the coordination between the heat pump with cooling function and the controlled residential ventilation with cooling function done?

Sorry for asking so many questions. But I find the solution very interesting.

Ok, so you have a brine-water heat pump with two ground probes. I assume it also completely handles heating (underfloor) and hot water preparation for you. Or are there additional system components? Can you say something about the acquisition costs and maintenance costs?

Exactly, a compact unit with an integrated hot water tank.
I wanted to keep the system as simple as possible, I have installed neither a buffer tank nor mixers, nor ERR. However, the preparations for these are located in the rooms and distributors.
The heat pump cost €8,000 plus connection, the deep drilling including all pipelines, shaft, and expert was €13,000. Unfortunately, these are/were very expensive in our area. The running costs consist only of the consumption, which in recent years has been between 3,100 and 3,500 kWh for 185 sqm of heated living space including hot water. In addition, we have a small photovoltaic system on the roof that covers part of the consumption.

Then you write that the controlled residential ventilation in your house also cools. Is an additional heat exchanger used or is it connected to the brine-water system? What are the conditions for the controlled residential ventilation? What air temperature comes out? Acquisition costs? Running costs?

The controlled residential ventilation has its own brine geothermal exchanger, consisting of a 100 meter brine line laid around the house during the cellar backfilling, a pump, and a heat exchanger.
Acquisition costs approx. €2,000
Consumption geothermal exchanger: 242 kWh per year
Consumption controlled residential ventilation: 570 kWh
The supply air temperature at 30°C outside temperature is about 20°C.

Honestly, your system would be my favorite if the cooling capacity is really sufficient. Otherwise, we would still end up with air conditioning possibly combined with solar on the roof, which significantly reduces running costs.

If a heat pump is planned anyway, you can test it without much financial risk; if the cooling capacity is not sufficient, you can always retrofit an air conditioner.

Otherwise, you have shutters or blinds on all windows. What is the orientation of the house? Many windows facing south, for example? Is there possibly natural shading? Big trees or the shadow of larger buildings falling on the house? Do you have an attic directly under the roof and if so, how are the temperatures there?
[QUOTE]
Shading is present on all east/south/west windows. There is no natural external shading (detached single-family house in a new development area).
Attached is a photo from the construction phase, the street side with the bay window is the south side. There is no direct attic, the rooms on the upper floor have a fairly high knee wall (just under 2 meters), the slopes and ceiling are directly insulated, the small attic is not insulated. The temperatures on the upper floor are basically similar to those on the ground floor, around 23°C. My wife still sleeps in her long pajamas even at 30°C outside temperature.

[QUOTE]
Oh yes, and how was the coordination between the heat pump with cooling function and the controlled residential ventilation with cooling function done?

There is none, the heat pump is controlled by outside temperature, the cooling activates from a certain average temperature. The geothermal exchanger of the controlled residential ventilation also switches on from a certain maximum or minimum temperature.

Sorry for asking so many questions. But I find the solution very interesting.

You are welcome to ask anytime [/QUOTE][/QUOTE]

I would simply choose the method for which the installer also guarantees to me, even at 40 degrees room temperature and 40 degrees outside temperature, that the room cools down to a comfortable 22 degrees within an hour.

I would simply choose the method for which the installer also guarantees, even at 40 degrees room temperature and 40 degrees outside temperature, that the room cools down to a comfortable 22 degrees within an hour.

Exactly. And that only works with a classic air conditioner. Period!

I would simply choose the method for which the installer also guarantees, even at 40 degrees room temperature and 40 degrees outside temperature, that the room cools down to a comfortable 22 degrees within one hour.

And when will this case ever occur? Why should one oversize a system like that? We still live in Germany and not in the desert.

And when will this situation ever occur? Why should one oversize a system like that? We are still living in Germany and not in the desert.

Sure, it is unlikely.. but we have already had 38 degrees over a longer period.. And in the next years/decades it probably won't get any cooler..