ᐅ Proper Settings for an Integrated Air-to-Water Heat Pump for Beginners

Hello everyone,

We moved into our KfW 40 new build in May. Now that it’s getting colder, I’d like to turn on the heating. We have an air-to-water heat pump with an indoor unit that includes a ventilation system, and so far only the domestic hot water and ventilation have been running. (Our consumption after 5 months is 3100 kWh.) Specifically, it is a Tecalor THZ 5.5 eco. We have about 140sqm (1500 sq ft) of living space over 3 floors with underfloor heating.

Just to be clear, I have no experience with heating settings and I’m trying to learn from the internet, which is quite difficult. As far as I understand, all room thermostats should be open and individual rooms are regulated elsewhere. But why? What exactly is this heating curve, the base point, etc.?

I would really appreciate it if someone could explain this to me in simple terms, or should I just leave it to the plumber? He just used standard settings.

I will write down our current values here. (Oh, and some settings are locked by a code I don’t know.)

Heating settings
Room temperature HK1 and HK2 (I think the plumber doesn’t know which heating circuit is which)
RT day 20.5°C (69°F)
RT night 17.5°C (63°F)
RT standby 10.0°C (50°F)
Heating circuit manual setpoint 35.0°C (95°F)

Heating curve HK1 and HK2
Slope 0.20
Base point 1.0°C (34°F)
Room influence 0
Proportion of flow temperature 30%
Target max value 55.0°C (131°F)
Target min value 10.0°C (50°F)

Basic settings
Proportional part 2.0%/K
Integral part - INV 500
Max partial load level heating 03
Max flow temperature heating 60.0°C (140°F)
Summer operation 17.0°C (63°F)
Hysteresis summer operation 4.0 K (7°F)
Outdoor temperature damping 12 h
Bivalence point -10.0°C (14°F)
Minimum runtime 20 min
Outdoor temperature correction 0.0°C (32°F)
Suppression of temperature measurement 60 sec
Heating design temperature -20.0°C (-4°F)
Heating design power 100%

Should I also provide hot water and ventilation settings?

I won’t go into the settings now, as this would be the 1,001st thread on the internet covering the basic settings of the Tecalor/LWZ.

Try searching for the Stiebel Eltron LWZ, as it is basically identical to the THZ, and you’re more likely to find useful information there.

Then read up further. It’s worth it, considering your consumption. For a KfW 55 building, we need just a bit more than half the energy over the whole year for heating AND hot water/ controlled ventilation.

3500 kWh over the summer months just for domestic hot water is already unusually high; there must be a serious issue with the settings if this is supposed to be only normal heating/hot water.
However, I would be interested to know how it is possible to consume less than 2000 kWh for heating and hot water throughout the entire year.

ASK0043 schrieb:

I would be interested to know how it is possible to use less than 2000 kWh for heating and domestic hot water throughout the whole year.

An energy-efficient new build or a properly renovated older house of moderate size. I can also easily stay below 2,000 kWh.

+ a properly operated heat pump. The internet is full of people who manage this. These are the ones who have taken the time to learn about it.

ringelstreifen schrieb:

Our consumption after 5 months is 3100 kWh.

Are you sure that refers to electricity consumption? I would rather guess it’s heat energy production. Otherwise, something would really be wrong with your system.

Since April, we have had about 450 kWh of energy consumption, but approximately 1600 kWh of heat energy production (heating + domestic hot water). Over the last 12 months, nearly 10,000 kWh of energy production and 2650 kWh consumption. Officially a KfW 70 house.

However, we also heat to 22°C (72°F) room temperature (yes, everyone here is a bit sensitive to cold), so I am quite satisfied.