Here is my brief experience report.
Maybe you could also share your experiences with functional heating? Duration, temperature, electricity consumption, etc.
Our cement screed was installed at the beginning of July. Exactly one week ago, the heating phase started – two weeks later than planned, because the customer service for commissioning the heat pump had no earlier appointments due to the holiday period. Not a big deal, in my opinion.
In our case, there was absolutely no dripping from the walls or windows immediately after laying the screed. The humidity was sometimes around 80%, it was muggy and hot (outside temperature over 30°C (86°F)), but you couldn’t see the moisture. Do you have an explanation for this? We plastered the whole house with pure lime plaster, and all walls are made of Poroton bricks. Could this contribute to better moisture regulation? Even with these amounts of water?
Both of my neighbors (one with Ytong blocks and the other a prefabricated house, each with gypsum plaster) had water running down their windows. They sometimes had to use Kärcher window vacuum cleaners to remove the water from the glass after every ventilation.
Regarding functional heating:
Yesterday, the underfloor heating reached 40°C (104°F). Room temperature 34°C (93°F)!!! Humidity before airing was 54%, after airing 58%!!! I think I can gradually skip airing 😉 . During the day, it doesn’t seem worthwhile. Today, I aired at 5 a.m. (!) and managed to lower the indoor temperature from 34.9°C (95°F) to 27°C (81°F). Unfortunately, with the current weather, airing during the day doesn’t work. Electricity consumption in the first seven days was 110 kWh, half of which was covered by the already connected photovoltaic system. The air-to-water heat pump cycles frequently and runs at a max of 2200 W (since 5 a.m. today without pause).
I’m curious about week two.
Maybe you could also share your experiences with functional heating? Duration, temperature, electricity consumption, etc.
Our cement screed was installed at the beginning of July. Exactly one week ago, the heating phase started – two weeks later than planned, because the customer service for commissioning the heat pump had no earlier appointments due to the holiday period. Not a big deal, in my opinion.
In our case, there was absolutely no dripping from the walls or windows immediately after laying the screed. The humidity was sometimes around 80%, it was muggy and hot (outside temperature over 30°C (86°F)), but you couldn’t see the moisture. Do you have an explanation for this? We plastered the whole house with pure lime plaster, and all walls are made of Poroton bricks. Could this contribute to better moisture regulation? Even with these amounts of water?
Both of my neighbors (one with Ytong blocks and the other a prefabricated house, each with gypsum plaster) had water running down their windows. They sometimes had to use Kärcher window vacuum cleaners to remove the water from the glass after every ventilation.
Regarding functional heating:
Yesterday, the underfloor heating reached 40°C (104°F). Room temperature 34°C (93°F)!!! Humidity before airing was 54%, after airing 58%!!! I think I can gradually skip airing 😉 . During the day, it doesn’t seem worthwhile. Today, I aired at 5 a.m. (!) and managed to lower the indoor temperature from 34.9°C (95°F) to 27°C (81°F). Unfortunately, with the current weather, airing during the day doesn’t work. Electricity consumption in the first seven days was 110 kWh, half of which was covered by the already connected photovoltaic system. The air-to-water heat pump cycles frequently and runs at a max of 2200 W (since 5 a.m. today without pause).
I’m curious about week two.
K
KarstenausNRW22 Aug 2023 20:54That is about 90% humidity at 28 degrees Celsius (82°F). So, a very muggy day. Nothing unusual.
You have roughly 24.8 grams of water in the air. A muggy day in the south at 30 degrees Celsius (86°F) and 70% relative humidity already contains 21.3 grams of water in the air.
With the values you mentioned, a tremendous amount of water has already evaporated from the screed.
You have roughly 24.8 grams of water in the air. A muggy day in the south at 30 degrees Celsius (86°F) and 70% relative humidity already contains 21.3 grams of water in the air.
With the values you mentioned, a tremendous amount of water has already evaporated from the screed.
X
xMisterDx4 Sep 2023 21:28I assume that your house has not been insulated yet or was not insulated before. That could explain the difference compared to your neighbors.
With Ytong, the block itself provides the insulation, while the prefabricated house has insulation within the walls.
With Ytong, the block itself provides the insulation, while the prefabricated house has insulation within the walls.
xMisterDx schrieb:
I assume your house hasn’t been insulated yet or wasn’t insulated before. That could explain the difference compared to the neighbors.
With Ytong, the block itself acts as insulation, whereas a prefab house has insulation within the walls. Actually, it is insulated. We are building with the filled Poroton brick MZ70 – so no additional insulation is applied to the facade.
By the way... the screed heating program is finished. The screed has cracked in two places – about 1 meter (3 feet) long but thin hairline cracks. The screed installer treated these with resin yesterday. He said that cracks like this are common and shouldn’t be too serious. Hopefully...
Regarding our electricity costs:
As mentioned above, our photovoltaic system is already running, and the heating was done using the air-to-water heat pump with a maximum supply temperature of 55°C (131°F)!!!
Two-way meter,
Reading before heating – 65 kWh
Reading on the last day of the program – 307 kWh
Consumption: 242 kWh!!!
The heat pump operated with an average COP of 4.6, and the electric heating element did not activate (due to the high outside temperatures).
During the heating period, the photovoltaic system fed an additional 415 kWh into the grid – it was almost constant rain for a week.
I’m very satisfied with these figures.
Similar topics