ᐅ Air-to-Water Heat Pump: Current Consumption and Data

We have "short distances" and deliberately no circulation.

Our heat pump has been running for 12 hours. It started up yesterday evening at 9:30 pm and it was only 2.5°C (36.5°F) last night.

Alessandro schrieb:

How did you set up your domestic hot water circulation? That can really be an energy guzzler.

Once a day for 20 minutes, because it needs to run, in the afternoon, ideally to trigger hot water generation during the warmest time.

I wouldn’t have needed circulation, but I wasn’t allowed to remove it by the general contractor 🙄

... and moving on here at the air-to-water heat pump discussion group 🙂

I have now analyzed my air-to-water heat pump in the 205m² (2200 sq ft) KfW55 house for one year, from November to October:
Electricity consumption for heating including hot water was 3300 kWh (separate electricity meter), with a seasonal performance factor (SPF) of 4.2. The SPF was slightly reduced due to a high standby power consumption for an oil sump heater integrated into the heat pump.

According to the internal heat meter of the heat pump, a total of 14,000 kWh was produced over 12 months (consisting of 12,100 kWh heating energy and 1,900 kWh hot water).

The SPF is as expected. However, the heating demand is somewhat higher than I had anticipated. Was I too optimistic, or are there hidden thermal bridges, or is the construction moisture in the new build increasing the heat demand in the first winter? We always kept the temperature around 22°C (72°F).

Do you have any comparison values?

For us, between October 31, 2020, and October 21, 2021, the electricity consumption was about 3,500 kWh, slightly higher than originally estimated. We have a total of 218 m² (2,347 sq ft) of heated living area. Generally, the indoor temperature is kept rather warm, around 22-23°C (72-73°F).

Electricity consumption: 3,500 kWh
Heat produced: 15,000 kWh

Coefficient of performance (COP): 4.28

Unfortunately, I cannot provide an exact figure for how much electricity is supplied by the photovoltaic system. It is certainly not more than 20%.

Here are my notes: 13,799 kWh heat output with 3,790 kWh electricity consumption included.

250 m² (2,690 ft²) KfW 70, but with timber frame construction, which is generally better. Household of 5 people, including 2 small children, so there is often an additional heater in the bathroom running on the same electricity meter. And a 300-liter (79-gallon) buffer tank, which still circulated during winter.

I think there is room for optimization in your case, with a hydraulic balancing.

halmi schrieb:

We have a total heated area of 218m² (2,347 sq ft). Generally, the indoor temperature is rather warm at around 22-23°C (72-73°F).

Electricity consumption: 3,500 kWh
Heat produced: 15,000 kWh

What energy standard do you have? Existing building or new construction? Interesting comparison values.