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

The performance factor at 8 degrees Celsius (46°F) outdoor temperature is really good, so no worries. In my case, the air-to-water heat pump also operated on a 6-hour cycle during the night.

Oetzberger schrieb:

The performance factor at 8 degrees Celsius (46°F) outdoor temperature is really good, so no worries. My air-to-water heat pump also ran in 6-hour cycles during the night.

Bookstar can handle a bit of teasing. The small difference in operating costs at those outdoor temperatures is acceptable. Although I can't distinguish between my on/off heat pump and the modulating components here. How much do your modulating heat pumps consume at the lowest setting?
Also, the temperatures plus rain are extremely beneficial for the garden established last year.

Zaba12 schrieb:
What power consumption do your modular heat pumps have at the lowest setting?

Good question... not so easy to answer, since I never really know what the lowest setting actually is. According to the datasheet, mine modulates between 1.7 and 8.6kW heating output. According to the photovoltaic portal, power consumption increases by about 400W when the unit starts up – and I’m just assuming that it starts at the lowest setting.
That corresponds to a COP of 4.25 (1.7kW heating at 400W power consumption), which is actually a bit low (the current average is 5.9 according to the heat pump display, which of course could be somewhat optimistic too). However, my heat pump is not yet optimized in the lower range (for example, both pumps run constantly at 70%, which leads to very low temperature differences – it would probably be better to control the pumps according to the output. I’m still waiting for an answer about whether/how this is possible).

Long story short: I estimate 400W as the lowest power consumption (and suspect there’s optimization potential at low loads).

Does that sound about right?

Otherwise, May in Sauerland is also cold, wet, and gloomy. Total electricity consumption (heating, hot water, household) in May so far is only 268kWh. Of that, 4kWh was drawn from the grid and 914kWh fed back... running smoothly :p

Hangman schrieb:

Good question... not so easy to answer, since I never really know what the lowest stage is. According to the datasheet, mine modulates between 1.7 and 8.6 kW (5.7 and 29.9 kBTU/h) heating output. According to the photovoltaic portal, power consumption increases by about 400 W when the unit starts up – where I simply assume it starts at the lowest stage.
That corresponds to a COP of 4.25 (1.7 kW heating at 400 W power consumption), which is actually too low (the average value is currently 5.9 according to the heat pump display, which could of course also be somewhat optimistic). However, my heat pump is not optimized at the lower end yet (for example, both pumps run continuously at 70%, which leads to very low temperature differences – it would likely be better to control the pumps depending on the load. The answer if/how that can be done is still pending).

Long story short: I use 400 W as the lowest stage (and suspect optimization potential in the lower power range).

Could that be accurate?

Otherwise, May is also really cold, wet, and gloomy in Sauerland. Total electricity consumption (heating, hot water, household) in May so far is only 268 kWh. Of that, 4 kWh were drawn from the grid and 914 kWh fed in... running :p

268 kWh are you sure? We’re at 407 kWh and the heating has been off since the end of April. The electric car is being charged more often now, but 140 kWh less and that with heating? For me, it’s grid consumption 7 kWh and feed-in 518 kWh.

Why do I always seem to get criticized here for using so little electricity? 😉

We are just two people, don’t have any energy-consuming hobbies, and the house/heating/water systems seem to work quite well.

I like my house. Outside the temperature is rising up to 30°C (86°F), but inside nothing changes.
This morning I aired out the house to normalize the humidity after what felt like six weeks of rainy weather. Even the mechanical ventilation system was overwhelmed in recent weeks.

Let’s see how it goes over the next few days.