ᐅ Correctly Setting Up a Heat Pump

Hello dear forum community,

we have been living in our single-family house (150 m² (1,615 sq ft) of living space) for several months now. We have underfloor heating throughout and heat with a brine-to-water heat pump (supported by heat recovery from the exhaust air system).

Because we have a photovoltaic system on the roof, we decided against having a second meter (peak/off-peak) and run the heating through the "normal" meter to use as much self-generated electricity as possible.
Therefore, I don’t have an exact overview of the heating consumption. With current sub-zero temperatures (-10 to -12°C (14 to 10°F)), our total daily consumption is about 30 kWh.

With that said, I would like to know if there is any way to optimize the settings of the heat pump to possibly reduce consumption.
A hydraulic balancing was done after commissioning, and every room has thermostatic valves (scale 1 to 5).
The heat pump is equipped with an outdoor sensor; I can adjust the heating curve and the so-called parallel shift.

Initial settings were: room temperature: 20°C (68°F), heating curve: 30°C (86°F).

There are instructions online about the adjustments. They say: open all thermostatic valves fully (to eliminate interference factors) and flatten the heating curve until the desired temperature is just reached.

But: should the thermostatic valves always be set to their highest level? Then I couldn’t regulate upward if I want to!?

What room temperature should ideally be reached at setting 3? 20°C (68°F)? Then the heating curve at 30°C (86°F) would probably be about right. But in that case, the actuator drives must constantly close the valves to "throttle" because otherwise, it would get too warm – and the generated heat is not used optimally? So would it be better to lower the heating curve and open the thermostatic valves more (5 in the bathroom, 4 in living areas)?

I appreciate any tips!

Best regards
James

James schrieb:
What room temperature should ideally be reached at level 3? 20°C (68°F)? Then the heating curve at 30°C (86°F) would probably be about right. But wouldn’t the actuators then constantly be closing the valves and “regulating down” because otherwise it gets too warm – meaning the generated heat isn’t used optimally? So would it be better to lower the heating curve and turn up the room thermostat fully (5 in the bathroom, 4 in the living areas)?

You’re asking the wrong question here. In my opinion, the right question is: “What room temperature do we want to achieve?” You’re in your own single-family home. You don’t have to stick to the standard 20°C (68°F) for living areas – do you feel comfortable at 20°C?
Our comfort temperature in the living room is 24°C (75°F). Since this is the warmest room, I set the thermostat there to 25 (it goes up to 30) and then adjusted the heating temperature of the heat pump accordingly. This was a process that took several days, because it makes a big difference whether the sun is shining or not. When the sun is out, it gets warm quickly; on fully cloudy days, we have “only” 22°C (72°F) in the living room – then, if necessary, I can increase it to “30.” But due to the slow response time of the heating system, this usually doesn’t make much difference – it just makes you feel better :o

Hello James,

I’ll make it a bit simpler and hope this helps with your problem. We also had some difficulties adjusting the heat pump at the beginning. Then a friendly heating service technician gave us the following tip during maintenance:

Choose a reference room. For us, it’s the bathroom, as the technician recommended. This makes sense since you usually want it warm there after showering or bathing. Set the thermostat in this room to maximum. The rest then adjusts based on this room. After that, you can set the heating curve and other thermostats as you like. This approach works very well for us.

Of course, another room can also be used as a reference.

Best regards from HB-Blog

Choose a reference room. For us, it’s the bathroom, as recommended by the technician. That makes sense since you usually want it warm after showering or bathing. Set the thermostat in that room to maximum. The rest of the system then adjusts based on this room. After that, the heating curve and all other thermostats can be adjusted as desired. This method works very well for us.

I’m also having trouble setting up the heat pump. That’s why your suggestion is very good and actually simple. I will try it the same way.
Thank you very much 😉

I also had difficulties with the setting. I tried it in the bathroom as well, and it worked well. After that, I had the right temperature in all rooms.

My tip:
The heat pump controller should and can manage the control of the supply temperature based on the outdoor air temperature. Existing room thermostats should ideally not perform any control function, meaning they should remain fully open, except in rooms that are not heated or only minimally heated. In these rooms, the room thermostat can limit the room temperature. The settings for this are usually:
Level 1: Frost protection
Level 2: 15-18°C (59-64°F)
Level 3: 18-21°C (64-70°F)
Level 4: >21°C (>70°F)
Level 5: fully open, no control.
The actual temperatures reached depend on the manufacturer and the spatial arrangement of the sensor.
It is important that the heating curve settings for slope and curvature match the building’s characteristics, and that the supply temperature always corresponds to the value the house needs to reach an indoor temperature of 20-22°C (68-72°F).
And: Are you aware that increasing the room temperature by 1°C (1.8°F) results in approximately 7% higher energy consumption?