ᐅ New heat pump to replace oil heating with existing radiators

For such an investment, I would at least get an alternative quote, preferably several.

All German heat pump manufacturers have a dealer locator on their websites. There you can find heating contractors who are familiar with heat pumps from that specific manufacturer. I would prefer that over a multi-level marketing structure.

A combination of an air-to-air heat pump and an air-to-water heat pump (air conditioning and water-based circuits) also seems strange to me.

R32 as a refrigerant will be banned in the future. So they’re probably in a hurry to sell their products.

How do you currently heat: radiators or underfloor heating?

6000 liters (1585 gallons) of oil and 14 kW heating capacity don’t really match; that doesn’t inspire confidence in the seller.

A room-by-room heat load calculation should be done.

ajokr2025 schrieb:

6000 liters of oil and 14 kW heating capacity

I think he will more likely get a 14 kW heat pump with a heating output probably about four times higher at this oil consumption.

tomtom79 schrieb:

I believe he will rather get a 14kW heat pump with a heating capacity probably about four times this oil consumption.

According to the datasheet, this is the nominal heating capacity at +7°C (45°F).

@ajokr2025 Thank you, I find your contribution highly efficient. If we could delve into this a bit more, it would really help me a lot. Here are some additional details: We do not have underfloor heating. Each room has 1–2 wall-mounted radiators, heated with oil, and with the mentioned annual consumption, both we and the tenant (a medical practice) stayed comfortably warm. It is a Bien-Zenker house (prefabricated house), which we built in 1990. At the time, the insulation was state of the art. A heating load calculation was done by the DWW representative for each room.
Annual performance factor 4.9, living area 316 sqm (3400 sq ft)
Estimated heating demand 58,860 kWh
Heating load according to DIN EN 12831: 15.2 kW
Required electricity 13,213.47 kWh
Pump rated power 12.3 kW
Refrigerant R32

In the building survey, each room is listed in the offer with many properties:
Floor area, exposed perimeter, ceiling height, room area, room volume, room envelope surface,
exposed perimeter, minimum outdoor air exchange, infiltration, airtightness level (ALD), adjacent temperature, U-value, heat loss,
thermal bridge allowance, and much more.
In 5 out of 10 rooms, an indoor unit with an air-to-air heat pump for heating and cooling (AERO duo comfort) is planned.

I have requested other offers, but all are far above the DWW price (according to KfW 21,000 €), the highest (a local company nearby) was at 60,000 € (which I cannot afford).

What’s your gut feeling?
Best regards
Norbert

That results in 48 W/m², but 4200 full operating hours. So the pump runs at full capacity for half a year. Alternatively, the oil heater may have warmed the surrounding area more than the rooms themselves.

strzata schrieb:

Seasonal performance factor 4.9

Where does that come from? Ground-source heat pump with an extremely low supply temperature in a new building – then yes. In an older building? That’s probably calculated optimistically to look good.
SCOP 4.9 only applies to the indoor units, i.e., the air conditioning units. For the hydraulic module, it’s listed as 4.0–4.2. Nothing is specified for the entire system.

strzata schrieb:

I have requested other offers, but all of them are significantly higher in price than DWW’s.

Hmm. If a very young company offers you a product today that is significantly cheaper than all competitors, you should be more than just skeptical. Because even these guys can’t work magic. A lower price is fine. But if it’s much lower, you will find a catch somewhere.
Every consumer protection agency warns: Be cautious with offers that are excessively cheap – regardless of the product.

There are already some genuinely negative reviews available online.

P.S. By the way, the heat pump is said to be a rebranded Hitachi product.