Unclog steam generation in High Oven

Firstly, we already know that there is enough water in the tank - we just calculated the amount, so no need to check.
Secondly, the drain should be performed before the fill, because we're replacing the same amount - otherwise, the oven clogs, unable to do anything.

Therefore, we do both of these - skip the check, and drain first.

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Make sure to pull #2 first