ᐅ Underfloor Heating on the Upper Floor – One Room Always Stays Too Cold
Created on: 13 Nov 2024 23:19
A
Allthewayup
Hello everyone!
I'm at my wit’s end. I just can’t get the children's room above 20.5 degrees Celsius (69°F), while all the other rooms on the upper floor reach between 21.5 and 22.0 degrees (71.5 and 72°F) with the same settings. The affected room also feels noticeably cooler.
I have slightly increased the flow rate, but with no success (+0.3 degrees). The valve is now 95% open but the room temperature remains unchanged.
Thermal imaging camera showed nothing unusual, no cold spots. I checked all window seals, also fine. Photos from the installation of the underfloor heating were reviewed, no issues visible. The hydraulic balancing has been done twice to rule out errors.
Two heating circuits of identical length run through the 17 sqm (183 sqft) room. Pipe spacing is 10 cm (4 inches). The supply temperature at 5 degrees Celsius (41°F) outdoor is 27 degrees (81°F). The heating curve is set at 0.35, so at 0 degrees (32°F) outside, the supply temperature is about 28.3 degrees (83°F). We have 22.2 degrees (72°F) on the ground floor, so the supply temperature cannot be the problem.
I turned off the mechanical ventilation for 24 hours, no change. Removed the carpet for 24 hours, no change. There is only a small wardrobe on the floor; the bed is a loft bed and does not affect the underfloor heating.
I don’t understand why this room stays noticeably cooler than the adjacent room (exactly the same conditions).
Do you have any ideas where the problem might be? I don’t want to raise the supply temperature for the 17 sqm if there is no reason to do so for the other 140 sqm.
I'm at my wit’s end. I just can’t get the children's room above 20.5 degrees Celsius (69°F), while all the other rooms on the upper floor reach between 21.5 and 22.0 degrees (71.5 and 72°F) with the same settings. The affected room also feels noticeably cooler.
I have slightly increased the flow rate, but with no success (+0.3 degrees). The valve is now 95% open but the room temperature remains unchanged.
Thermal imaging camera showed nothing unusual, no cold spots. I checked all window seals, also fine. Photos from the installation of the underfloor heating were reviewed, no issues visible. The hydraulic balancing has been done twice to rule out errors.
Two heating circuits of identical length run through the 17 sqm (183 sqft) room. Pipe spacing is 10 cm (4 inches). The supply temperature at 5 degrees Celsius (41°F) outdoor is 27 degrees (81°F). The heating curve is set at 0.35, so at 0 degrees (32°F) outside, the supply temperature is about 28.3 degrees (83°F). We have 22.2 degrees (72°F) on the ground floor, so the supply temperature cannot be the problem.
I turned off the mechanical ventilation for 24 hours, no change. Removed the carpet for 24 hours, no change. There is only a small wardrobe on the floor; the bed is a loft bed and does not affect the underfloor heating.
I don’t understand why this room stays noticeably cooler than the adjacent room (exactly the same conditions).
Do you have any ideas where the problem might be? I don’t want to raise the supply temperature for the 17 sqm if there is no reason to do so for the other 140 sqm.
A
Allthewayup20 Nov 2024 21:54I am currently waiting for the electrician to review the wiring of the heating system and for the heating engineer to check the rest of the installation.
The question of removing the EER is a matter of philosophy. If you ask 10 installers, you will get 10 different opinions nowadays. Besides the hydraulic balancing, many other factors come into play, such as the heating curve, parallel shift, system setup (buffer tank yes/no), and so on. That is why I consider the blanket statement “remove EER” too vague. It may be useful in many cases but is by no means the ultimate solution in every situation.
The question of removing the EER is a matter of philosophy. If you ask 10 installers, you will get 10 different opinions nowadays. Besides the hydraulic balancing, many other factors come into play, such as the heating curve, parallel shift, system setup (buffer tank yes/no), and so on. That is why I consider the blanket statement “remove EER” too vague. It may be useful in many cases but is by no means the ultimate solution in every situation.
Allthewayup schrieb:
yellow = office (10m² (108ft²)) target = 20, actual = 22.2
green = bedroom (17m² (183ft²)) target = 21.5, actual = 21.5
red = child 1 (17m² (183ft²)) target = 21.5, actual = 19.9!
purple = child 2 (12m² (129ft²)) target = 21.5, actual = 21.5
blue = bathroom (12m² (129ft²)) target = 22, actual = 21.9
Thermal balancing was done two weeks ago; a friend who is a heating technician helped me. Since there was no improvement, I reset everything to factory settings.
I don’t understand why heating circuit 2 in the bedroom is mostly closed, while heating circuit 1 is running continuously.
*Edit
The heating pump is running at full power (40W). All this suggests that the thermostats do not match the rooms and that something was wired incorrectly. We had the same issue with our new build. It took me weeks to figure it out because you naturally trust the labeling.
At some point, I got fed up and manually turned on only one heating circuit per day while keeping all others off. Then I checked which room was warming up and took notes. Repeat that with every circuit. This process can take one to two weeks, but you have to be patient since underfloor heating responds very slowly.
Alternatively, turn all heating circuits on (lower all actuators, but label them first!) and check if the green child’s room warms up. That may not work, because you might need higher valve opening degrees (VLT) to reach full heating power. This means you may not notice a clear effect.
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Benutzer 100121 Nov 2024 21:24Allthewayup schrieb:
Meanwhile, I am waiting for the electrician to check the wiring of the heating system and for the heating engineer regarding the rest of the installation.
The topic of removing the EER is a matter of philosophy. If you ask 10 installers, you will get 10 different opinions nowadays. Besides the hydraulic balancing, many other factors come into play, such as the heating curve, parallel shift, system setup (buffer tank yes/no), etc. That is why I find the blanket statement "remove EER" too vague. It may be useful in many cases but is by no means the best solution in all situations. Your statement shows that you do not understand the purpose of these components.
A buffer tank never plays a decisive role for the rooms. The buffer regulates the return flow temperature, delaying it back to the heat pump. The best buffer is your screed; this mass cannot be replaced by any buffer tank.
The parallel shift is the temperature adjustment based on the outside temperature during transitional seasons.
The heating curve is the only factor that influences the room temperature in all rooms.
To determine the correct curve without interference from any actuators, the EER must be removed.
And again, if you ask 10 installers, 9 out of 10 will say "we have always done it this way." And that is exactly the mistake.
Learn and understand for yourself.
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