Quote Originally Posted by eesakiwi View Post
I have a few car aircon radiators put aside for a similar project, the cores are Ali & about 10 x 10 x3.
I figured to puit 3 in a row in a box & pipe the cold water thats coming into the house, or the cold water thats going into the water heater thru it.

In reverse, I could pipe the waste hot water from the dishwasher (its HOT!) to heat up a room in the winter.
Not even going to go into why this will not work, but it will be a good lesson.