ᐅ Heat Pump vs. Heat Pump with Domestic Hot Water Heat Pump

Hello everyone,

I would like to get some opinions.
We have purchased a prefabricated wooden house from 1977.

The exterior wall, as well as the first-floor ceiling and attic floor, have 8 cm (3 inches) of insulation.

We want to improve the insulation of the basement ceiling and the attic floor afterwards.

A heating load calculation will be done beforehand.

We are a household of three people and consumed on average 1.625 m³ (57 cubic feet) of hot water per month in 2024. That is about 18 liters (5 gallons) per day per person.

Now to the main topic:
We are considering whether to install a heat pump or a heat pump plus a separate domestic hot water heat pump.

The advantage of the latter is that the heat pump can be smaller and therefore more efficient.

The disadvantage I see is having two devices that can fail instead of one?!

ShanghaiTang schrieb:

The advantage of the latter is that the heat pump can be smaller and therefore more efficient.

No. You basically size the heat pump according to the heating load, since the heat pump does not heat during domestic hot water production. So it does not do both at the same time.

Two heat pumps ultimately mean double the cost without added benefit. No advantage.

Or do you have special circumstances?

Do you have an example of a special feature?
I am not aware of any special features.

Thank you very much for your contribution. That helps me a lot.

ShanghaiTang schrieb:

Do you have an example of a specific issue?

(Damp) warm basement. The domestic hot water heat pump is installed indoors and requires heat. It cools the rooms and dehumidifies them in the process.

Ah, okay, no, the basement is unheated.

My neighbor is happy that his unheated basement is now much drier. It is also about four degrees Celsius (7°F) cooler, but no longer musty.