There exists a bug in liquid heat and temperature when liquid flows vertically that the total heat of the system loses during flowing(Verson AU-219035). By using this bug a player can cool quantities of hot water from steam geyser to room temperature easily, so it will have a bad influence on the balance of the game. Here I'll show you 2 examples on how to make use of this bug.
4.repeat this several times and you get a pool of cool water. (I repeated 3 times and cooled the water to 294K )
9t 280K water cooled 132t 393.15K water to 294K. That's impossible in real world's thermodynamics, so there is a bug in heat transferring.
1.Prepare insulated walls, vacuum surroundings and cooled ladders(granite for high heat compacity and conductivity).
2.Pour hot water from above. First level of the ladder were heated to 358.8K.
As you can see in the pic, the temperature suddenly dropped to 313K and if you lower the flow rate of water the temp change will be larger. Apparently 200kg of granite ladder cannot absorb so much heat, so a large quantity of heat just VANISHED during the heat transfer process. Players can use this method to cool hot water with low flow rate easily.
Steps to Reproduce
I write the whole process down in the description part because in this part you cannot insert pics. Just do as I do in the description part you can easily reproduce the bug.
This issue has not been confirmed by a developer yet.