system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does a washer-dryer combo use twice as much water when washing and drying compared to just washing?

Drying should be the complete opposite of using water...

I'm looking at specification sheets of washer-dryer combo units and this seems to be always the case.
gpt
In a normal standalone dryer, the hot moist air from the dryer is either vented outside, or is run through a compressor to cool down and release the moisture.

In a washer/dryer combo unit, they instead cool the air using cold water, since a water supply is already present on the unit.