Benutzer200
2021-12-03 09:14:49
- #1
Do you mean that 60 degrees must also be reached during the functional heating when the heating will only reach a maximum of 35 degrees in operation?
I have always read otherwise. DIN1264-4 also says raising to design temperature for 4 days.
There are two answers to your question:
1 (formally correct): Heating up to 60 degrees is mandatory, as only then the warranty applies.
2 (reasonable/practical): Heating up to 60 degrees is nonsense for underfloor heating designed for max. 30-35 degrees.
If the surface readiness heating as well as the preceding functional heating are not operated with the maximum possible flow temperature, the surface readiness of the screed can also be achieved, but due to the greater screed thickness between the heating elements, it will not be reached within the required timeframe.
This means: when laying the floor covering, the screed does not have the necessary dryness in cross-section.
That is correct, but not disastrous. Then heating will take longer and every floor layer will measure the moisture of the screed. Therefore – with a decent craftsman – the risk is zero.
If the specifications that represent the current state of the art as well as the rules of the trade are deviated from, the risk that the screed will be damaged is very high.
The problem is that these rules still do not include underfloor heating with 30-degree flow temperature but generalize.
Conclusion: for functional heating and surface readiness heating, you must reach the 60 degrees for the warranty, unless the screed layer guarantees it at lower temperatures. Otherwise, you have no practical disadvantages, since the function of the screed is tested at max. flow temperature (+5 degrees).
I have to strongly disagree with that serious problems will occur if you do not reach 60 degrees. Literature increasingly also speaks of "up to 55 degrees or the intended maximum flow/design temperature." Thus, there is a growing realization that it also makes sense to deviate from regulations. It changes from "maximum possible flow temperature" to "intended max. flow temperature."