Copper is a very good conductor of heat and is usually the material of choice where high heat transfer is required - so you'd expect to find it used in an evap. It is easy to solder and repair, compared with aluminium. It is stronger. It is heavier. It is also more expensive ...

As for why anyone would make a core out of aluminium, I suspect you will find the answer is merely the fact it is cheaper to make. Maybe the reason is that it's easier to make the core stand up to high pressures than copper, but I doubt it. Anyone know the reason?

I am curious to hear more about an "air restrictor" for the blower motor. I assume the reason that air is allowed into the motor is to cool it, how can restricting the hole, reduscing the airflow INCREASE the life of the motor.

Puzzled....

KP