ᐅ Operating Costs of Air-to-Water Heat Pumps: Consumption and Defrosting

Hello everyone,

For four days now, the heat pump (air-to-water, KfW55 standard) in our new building has finally been running, and during this time we have noticed that it
a) consumes around 70 kWh of electricity per day,
b) defrosts about 30 times during the day, roughly every 40 minutes (sensor-controlled, and the fins are constantly white), and
c) is continuously very loud.

Currently, there is no hot water consumption as the house is neither occupied nor are the sanitary installations finished. Only the heating is running. Does anyone have an idea what might be causing this and what can be done about it?

From what I read yesterday, defrosting should only occur every few hours, and the heat pump was sold to us with an estimated annual operating cost of about €700. With the current consumption, that would be reached in one month...

Hello
With the missing information, we can only guess.
Which heat pump, what size, heating load of the house?
How is the hydraulic integration done: directly into the underfloor heating, large buffer tank, separation buffer, combined buffer?
How is it operated, heating curve, ERR active?

Regards

Daniel-Sp schrieb:

...with the missing information we can only guess....

The information I currently have is

• Which heat pump: Thermia iTec eco 8
• Size: 8kW
• Heating load of the house?: 5.9kW
• How is the hydraulic connection configured: directly into the underfloor heating
• How is it operated, heating curve, ERR active?: I have no idea at the moment. The filling and initial commissioning by the heating engineer took place earlier this week. The room thermostats are not yet installed, so the heat pump is probably running on a fixed setting.

Thank you and best regards

What condition is the house in?
Is the shell completed?
Is the screed still wet or already dry?

RotorMotor schrieb:

...What condition is the house in?...

Everything around the house is completed, such as insulation, plaster, etc. The screed is dry; it was heated last October. Inside, the tiles are currently being installed, so part of the floor is already covered while another part is not. Basically, only plumbing/water installations and painting are left. Everything else is done.

Sven2617 schrieb:

that it
a) consumes about 70 kWh of electricity per day,
b) defrosts around 30 times during the day, approximately every 40 minutes (sensor-controlled, and the fins are constantly white), and
c) is continuously very loud.

Currently, none of this is normal – in my case, defrosting is scheduled every 1.5 hours (at night).
You should speak directly with the installer. Also, ask why an oversized heat pump has been installed.