The water heater in my house can be set all the way to 85c and it's right behind my kitchen tap, so it gets to that temperature within seconds. I've been wondering for a while if I could use it to just make tea instantly instead of putting the kettle on first, especially since I've read multiple times that 100c water is actually bad cause it can burn the tea leaves.

So far I haven't been able to try it because of some circumstances, but I might in the future.