Hello everyone,
While heating up our screed, I noticed that water was dripping from the ceiling at one spot. The heating technician broke open the screed where a coupling had been installed, but everything was dry there. I was told that if water had leaked, the pressure of 2 bar (29 psi) would have gone directly to the basement since the special electric heating system used to warm up the screed doesn’t have an expansion tank. We suspected the water might have come from the roof because there had been heavy rain at the time and the roofer was sealing the roof.
After the flow temperature reached its highest value, the dripping stopped. Now the temperature is dropping and currently is at 30°C (86°F). I have noticed that the pressure in the underfloor heating system has fallen from 2 bar (29 psi) down to between 1.3 and 1.5 bar (19–22 psi): 1.3 bar (19 psi) at the manifold on the upper floor and 1.5 bar (22 psi) at the heating unit. Yesterday, the flow temperature was 35°C (95°F) and the pressure was about 0.1 bar (1.5 psi) higher at both points.
My current assumption is that when the water was heated, it expanded and leaked somewhere in the underfloor heating pipes. Now that the temperature is falling, the pressure drops as well, because there is less water in the system. Our floor area is about 200 m² (2,150 ft²), so there is at least 100 liters (26 gallons) of water in the underfloor heating. When heated from 20°C (68°F) to 50°C (122°F), the volume increases to about 101 liters (27 gallons). This 1-liter (0.26 gallon) increase roughly corresponds to the amount that dripped from the ceiling.
Is it normal for the pressure to drop when the temperature decreases after functional heating, or could my assumption be correct and there is a leak somewhere in the underfloor heating system?
so long..
While heating up our screed, I noticed that water was dripping from the ceiling at one spot. The heating technician broke open the screed where a coupling had been installed, but everything was dry there. I was told that if water had leaked, the pressure of 2 bar (29 psi) would have gone directly to the basement since the special electric heating system used to warm up the screed doesn’t have an expansion tank. We suspected the water might have come from the roof because there had been heavy rain at the time and the roofer was sealing the roof.
After the flow temperature reached its highest value, the dripping stopped. Now the temperature is dropping and currently is at 30°C (86°F). I have noticed that the pressure in the underfloor heating system has fallen from 2 bar (29 psi) down to between 1.3 and 1.5 bar (19–22 psi): 1.3 bar (19 psi) at the manifold on the upper floor and 1.5 bar (22 psi) at the heating unit. Yesterday, the flow temperature was 35°C (95°F) and the pressure was about 0.1 bar (1.5 psi) higher at both points.
My current assumption is that when the water was heated, it expanded and leaked somewhere in the underfloor heating pipes. Now that the temperature is falling, the pressure drops as well, because there is less water in the system. Our floor area is about 200 m² (2,150 ft²), so there is at least 100 liters (26 gallons) of water in the underfloor heating. When heated from 20°C (68°F) to 50°C (122°F), the volume increases to about 101 liters (27 gallons). This 1-liter (0.26 gallon) increase roughly corresponds to the amount that dripped from the ceiling.
Is it normal for the pressure to drop when the temperature decreases after functional heating, or could my assumption be correct and there is a leak somewhere in the underfloor heating system?
so long..