"The heat has to go somewhere"
ok, and that translates into it heating up the room more how?
Your GPU on air will hit say, 80C under full load (example of course) that's 80C air that's just being blow around in your room and inside the computer.
The water will take away that heat long before it gets to 80C and will keep it at around 45C....any heat in the water will be transferred to the radiator which will be very quickly cooled by the fans....you're taking away 35C of heat just from one component alone right there.
Oh wait heres the main thing to notice.....hmm I've had both AIR and WATER, so I think I'd know exactly how it effects the room that the computer is in being that it's been in the same room during both instances.
You're trying to say that a hotter CPU and GPU under air, in which that heat is being directly blown out, is somehow cooler than a water setup which keeps the heat from rising to the levels of AIR in the first place and is kept within the water, inside the tubes, which yes gets to the radiator which is cooled...that radiator gets NOWHERE NEAR as hot as the heatsinks for your CPU and GPU.
So, you're burning more energy in your room by keeping water cooling running, AND, you're just moving the heat more efficiently from your computer to your radiator, which helps heat your room just as much.
burning more energy...ok, this isn't your body after eating a meal, or a furnace and coal we're talking about here.
"Moving heat" to the radiator doesn't heat up your computer at all....it's moving less heat than if you're just using air to blow it from the actual heat source...beyond that, yes the pump does of course produce it's own heat, but it's completely negated by the amount of heat you're dissipating from your GPU and CPU.
You guys are going off what you simply 'think' is correct and I've actually had both kinds of setups