heater hose connection

I'm pretty sure the feed side is from the hot intake and it returns to the pump for another trip thru. This way the core always sees the hottest water. This is also why, if I'm bypassing the heater I plug that hose so it cannot go back thru the pump and dilute/pollute/corrupt the incoming cold water
At the heater core, the small pipe, or the left pipe (from the engine side view) is the hot-side, or where I hook the intake to.