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
C
chewbacca123
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.
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.
Alessandro schrieb:
In post #686, your temperature differential is only 2.8K.
Can you adjust that anywhere?
The return temperature setpoint of 26.6°C (80°F) at an outdoor temperature of -3°C (27°F) also seems very low to me. The system uses an air pump. I don’t think I can adjust the temperature differential anywhere, right? The return temperature setpoint is calculated based on the heating curve. Although it is low, according to comparisons it is definitely within an acceptable range.
I will now let the system run like this for at least 24 hours and hope that my manual pump control does not cause any errors or, worse, damage the system completely…
Alright. I stumbled over the source temperature. The room temperature can definitely be correct. It’s possible that the heating curve no longer fits with the current outdoor temperatures and little sun. Do you have a comparison to last year? Sorry @Bookstar, but I don’t have your entire history in mind.
Joedreck schrieb:
All right. I stumbled over the source temperature.
The room temperature can definitely be correct. Of course, it might be that the heating curve no longer matches the current outdoor temperatures with little sun. Do you have a comparison to last year?
Sorry @Bookstar, but I don’t have your full history in mind. No problem, just ask. I appreciate any help.
I am quite convinced that the issue lies with the flow rates. Normally, the heating system runs at a maximum of 800 liters per hour (211 gallons per hour). In my view, that’s far too little for a house with 200 m2 (2,150 square feet) of heated area. That’s why almost nothing reaches the upper floor.
Since I switched to manual today, the room temperatures have shot up. The dining room was 21°C (70°F) this morning; now it’s already 21.8°C (71°F).
I will keep an eye on it. Although I believe the pump in modulating systems should actually be set to automatic, for testing purposes I have no choice but to leave it on manual for now.
A
Alessandro12 Jan 2021 12:38My heat pump modulates the flow rate between 780-960 L/h at -3°C (27°F) ambient temperature with an output of about 5 kW for a 200 m² (2,150 ft²) house.
I can adjust both the compressor output and the heating curve in technician mode.
It would be interesting to know if you can do that as well and what compressor output is currently set.
I can adjust both the compressor output and the heating curve in technician mode.
It would be interesting to know if you can do that as well and what compressor output is currently set.
T
T_im_Norden12 Jan 2021 12:55Err are, I assume?
The operating time should be several hours up to continuous.
If you have been running the heat pump at a minimum capacity of 60% the whole time until now, it is not surprising that the runtime is short.
The operating time should be several hours up to continuous.
If you have been running the heat pump at a minimum capacity of 60% the whole time until now, it is not surprising that the runtime is short.
T_im_Norden schrieb:
Errors, I assume?
The runtime should be several hours or continuous.
If you have been running the heat pump at a 60% minimum capacity the whole time, it’s not surprising that the runtime is short. No, it has always been set to Auto until now. I only have 2 compressor starts per day, which I think is very good.