ᐅ Underfloor heating with an air-to-water heat pump. House gets too warm when the sun is shining.

Created on: 4 Dec 2019 14:18

Hello everyone,

I have a general question.

We moved into our new build four months ago. The living area on the ground floor has three large floor-to-ceiling windows facing south. We have underfloor heating and an air-to-water heat pump.
It provides a really comfortable temperature inside the house, but we have a problem – whenever the sun is shining in winter, even if it’s -2°C (28°F) outside, the temperature suddenly rises to 24°C (75°F) in the living room. It gets uncomfortably warm in here, and the underfloor heating can’t be turned down quickly.
Should we assume that the large floor-to-ceiling windows are responsible for the heat gain? A photo of the south-facing side of the house is attached.
What would you do – always lower all the blinds as soon as sunlight is forecast? That seems quite annoying...
We have motorized blinds controlled by Somfy. Would you consider buying a sensor that automatically lowers the blinds at a certain temperature?

Thanks in advance for your replies.

Neues zweistöckiges Haus auf Baustelle mit weißer Blockfassade, pinker Dämmung und großen Fenstern

Daniel-Sp16 Dec 2019 18:04

#163

Do you know how to adjust the flow rates?
Pull up the red part on the flow tube at the bottom. Below that is a small black locking wheel—loosen it, then you can turn the flow meter at the top to open or close it.
You can also watch this on YouTube.

chewbacca12316 Dec 2019 18:09

#164

Daniel-Sp schrieb:

Hard to tell from the photo since it was taken at an angle, but it looks like more than 2.5. My floats look a bit different; I would use the red "disc" as a reference...

I also find it difficult to determine. Is the top edge of the float the actual volume? There is a white round ball on top with a red “cover.” Is the top edge of the white ball the volume?

chewbacca12316 Dec 2019 18:10

#165

Daniel-Sp schrieb:

It’s a small bathroom with a desired temperature below 20°C (68°F). Is there a shower in the 4 m² (43 sq ft)? If so, it probably isn’t used.
Even if the mixed return temperature shouldn’t be raised significantly, the small heating circuit reduces flow in the other circuits due to its low resistance. At least my initial suggestion for this heating circuit wasn’t that bad.

The shower is basically not used, more intended for guests, but how often does anyone actually stay overnight with us—almost never, maybe 1–2 times a year.

Daniel-Sp16 Dec 2019 18:15

#166

This is how it looks in my place.
Unfortunately, the heating is currently turned off.