Hi Eirik and welcome!
Effekt blir storre enn 4800 W and…
…are not the same. Just for info.
As @Peter_Kawa already mentioned, please don’t use the build-in delay flow cards for this use case. Beside the reason explained by Peter, another reason is that every time when the power becomes greater than 4.8 kW, the flow is triggered and the build-in delay flow cards are started again, even if the previous time has not yet expired. So if a delay is already running and after e.g. 5 minutes the power exceeds 4.8 kW again, the delay is started the second time and the first delay will not be stopped! It’s the same as with dominoes. Once the first domino has been pushed, the chain reaction can no longer be stopped.
In this post I tried to explain already, why the build-in delay card can lead to an unwanted behavior. It’s just in German, but with a translator I guess it will be understandable. If not, just ask.
My suggestions is to use a timer app like the Chronograph app, and this is an example flow just to turn off the heating after 20 seconds:
