In the case of
an excess of in-flow of a leaking tank, it is a mistake to think that it will
definitely overflow.
At first, an over-filling of the tank leads to an increase in the water level.
But, as the level climbs, the pressure on the leak increases and the out-flow
ends up equaling the in-flow.
The level of water will thus stabilise.
The in-flow is superior to the out-flow, these flows end up being equal
In the case of excess heating output excess in a home, we have no risk
of melting!
At first the heating excess will lead to a rise in ambient temperature.
But, as this temperature increases, the difference between interior &
exterior temperature increases and so heat losses increase as well.
When these are the same as the heat output, the ambient temperature level will
stabilize.
The heating output is superior to the heat losses, these outputs end up being equal