ᐅ Hot Water Only with a Heat Pump?

Hello everyone,

A friend has a new KfW-70 house with a heat pump for heating (underfloor heating) and domestic hot water, but no solar thermal system, no photovoltaic system, and a fireplace without connection to the heating system, as well as no other energy source. Is it possible to heat the water to the required temperature without activating an electric heating element? Is heating the water to 60 degrees Celsius (140°F) still necessary nowadays?

Yes, there are compact units available where the hot water tank is integrated – a legionella prevention program is recommended (with an electric heating element).

You don’t need a compact unit for that – just place a storage tank next to it, and that’s fine. With Vaillant, the volume is ridiculous anyway (not to mention the price).

A legionella program isn’t necessarily required for a single-family house – it depends on the usage habits 😉

So, what exactly is your question? This is what is being installed in millions of houses nowadays...

I didn’t mean that it’s necessary; I was more referring to the fact that there are even 2-in-1 devices for this directly from the manufacturer 😉 and yes, the volume is disappointing :\

If domestic hot water is generated on demand, in my opinion no legionella prevention program is necessary. In that case, it is sufficient, in my view, to heat the water to the desired use temperature, something just above 40°C (104°F) perhaps. After all, no one showers with hotter water, right?