Heat Issue - 2003 Honda Odyssey

Hello, you definitely must ensure after all those parts were replaced that you do not have any air still in the cooling system. Purge the air safely of course, and recheck operation. Further than that, you'll have to see if the engine temperature is getting hot enough utilizing a high quality diagnostic tool that can monitor engine temperature, and then check inlet and outlet heater core hose temperatures. Once you verify all that is providing sufficient and consistent temperatures, focus attention on the climate control system operation. Something will turn up.