What is the primary role of the heater tap?

vas85

SupraNut
Sep 29, 2006
391
0
0
Sydney, AU
Hey guys,

Simply as above... curious what it's primary role is.. as I've installed temporary brass plumbing in the location of the current heater tap, but I am still able to cool and heat the interior of the car... which sounds odd as if you have it bypassed it should always be heating...

What exactly does the heater tap do? (is there another heater blade that directs to suck from the heated rows or clean fresh air for coolness?)