just got a '72 convertible ac car
the heater hose is looped
don't connect to heater core
should i assume that whoever rebuilt this car's motor
was lazy or broke and knew haeater core is bad but did nothing
OR hook it up and risk the mess on the new rug and stuff
some one make my decission for me ............i'm tired of fliping that coin

If you don't need a heater, I would probably leave it alone. But, if you want to use it, I would suggest laying some plastic and a couple of old towels on the floor below the heater core and hook it up to see if it leaks. If you need to replace the heater core there is a thread in the "heating, cooling systems" forum that gives a good explanation of how to do it with pics.
heater core replacement on 73 w/A/C

Al,

I suspect that a P.O. did the loop to try and keep some heat out of the cockpit. It has the same effect as the shut-off valves folks have installed in the heater lines to limit coolant flow through the heater core when the heater isn't needed.

But I have also used that trick to keep from flooding the interior after a heater core blew and I didn't have the money for repairs right away.

Before hooking it back up the right way I'd suggest pulling the heater core and have it tested. In this case an ounce of prevention is worth a couple of gallons of mess!

I THINK I HAVE AN "" INVENTION "" TO TRY AND PUT SOME AIR THRU THE SYSTEM TO CHECK FOR LEAKS I'M UNSURE OF MAX #'S OF PRESSURE
SOME SAY 17#'S WHAT DO YOU THINK ???

Most cooling systems run with 10 to 15 lbs pressure. I think to pressure test your heater core I would not go over 15 psi.
If you can figure out a way to put a gauge in line, put around 10 to 15 psi in and let it sit for 5 minutes and see if the gauge drops. As long as all connections are tight and there are no leaks in the core, or the hoses, it should hold steady. Good luck.