ᐅ Comparison of Geothermal Heat Pump and Air-to-Water Heat Pump

There are all-in-one units designed for indoor installation, but they are quite bulky. However, if you have enough space, they could work. I believe noise shouldn’t be an issue with proper decoupling.

I’m opting for an outdoor unit. Since my property has an inconvenient side (access with pedestrian, vehicle, and utility rights of way to the neighboring property), I’m not too concerned about the appearance. You can also hide it with plants, although, of course, you cannot let them grow directly on the unit.

For me, gas is not an option, especially since there is a clear political intention to phase out all fossil fuel burners. With the carbon tax starting in 2025, a heating consumption of 10,000 kWh would incur about 110 EUR in carbon charges alone. That might not seem like much at first, but it will continue to increase. Whether LPG or other fuels will offset this by lower raw material prices is uncertain. It’s conceivable that the carbon tax will rise even further if consumption does not decrease.

Ybias78 schrieb:

With good arguments, I wouldn’t be against an air-to-water heat pump.

There are plenty of solid reasons in favor. What exactly don’t you like about an air-to-water heat pump?

I’m about to install two units in a two-family house. They are monoblock systems with a COP of nearly 3 at -10 degrees Celsius (14°F) outdoor temperature (4.9 according to the annual performance factor calculator). What more could you want? Each costs around €5,000 in materials (heat pump/domestic hot water storage and all necessary components like pipes, expansion vessel, heat meter, etc.). Then you still get funding deducted (planned 40% due to KfW 55 renovation).

They placed our indoor unit here on a pedestal, directly on the raw floor, even before the screed was poured. I assume this is for sound decoupling (?). The silver plate is still sticking out after the screed has been applied.

I can only emphasize again that the correct design of the underfloor heating is far more important than the choice of the heat generator.

I can replace the heat generator without much effort, but not the underfloor heating.

My underfloor heating is designed for a maximum supply temperature of 30°C (86°F), with all circuits roughly the same length, the longest being two loops of 90 meters (295 feet) each in the bathroom.

This allows me to switch from gas to a heat pump without any problems if necessary.

The house is equipped with mechanical ventilation with heat recovery, designed so that I do not need solar thermal panels on the roof to comply with the energy saving regulations (building permit / planning permission).

T_im_Norden schrieb:

I can only repeat that the correct design of the underfloor heating is significantly more important than the choice of the heat generator.
I can change the heat generator without much effort, but not the underfloor heating.

I completely agree. Reducing the spacing of the underfloor heating pipes from, for example, 15cm (6 inches) to 10cm (4 inches) costs only a few hundred euros but offers huge benefits.

T_im_Norden schrieb:

The house is designed with controlled residential ventilation and heat recovery so that I do not need solar thermal systems on the roof to comply with the energy savings regulations.

That sounds really interesting because gas could still be an option for us, although liquefied petroleum gas. So far, I haven’t come across how to comply with the energy savings regulations without solar thermal. Could you share some details on how it is possible to “bypass” this solar requirement or achieve the necessary values?