Purpose of a heater core?

[Gotz Cb7]

Not sure where to place this, so Off-Topic is where it goes, even though it sorta is Technical.

What the hell is the purpose of a heater core? Reason I'm asking, is because I'm in the process of replacing mine. I got it out, and installed the new one this evening. Just have to put the dash back on tomorrow. (whoever said you can get to the heater core with only taking the glovebox off.....HAHAHAH, are you God himself? Impossible).

This thing runs off anti-freeze? 2 lines....in/out for Anti-freeze. What's this have to do with heat? Why'd it kill my heat? Doesn't make any sense to me.

[The G-Man]

If you want the cabin to be warm in the winter, you need a heater core.

It uses the hot engine coolant flowing through it to put hot air in the cabin.

[AccordReborn]

its a radiator for the inside of your car. Hot water circulates through it. Its a part of your cooling system. Fans blow cold air through it and it heats the air through the process of conduction. The hot air then comes out your vent holes.

[Gotz Cb7]

So, this is part of the coolant system, but isn't the coolant system used to cool the engine? I think that's the part I didn't understand.

So, with my heater core bein' bad, could it be the cause of my car overheating when it's 80-90 degrees with a thermostat in? (both fans runnin' on a toggle).

[The G-Man]

The cooling system is not aiming to cool the engine like you are thinking.

Friction of all the moving parts creates immense amounts of heat, the cooling system just regulates this temperature and keeps it around 250 degrees Fahrenheit or so.

If your car starts to overheat for some reason during the summer, you can turn the heat on full blast to take some of the heat out of the coolant to avoid damage to the engine.