Low heat 98 Cherokee 4.7L

I just changes the heater core, water pump and thermostat and I only get luke warm heat coming out of the vents. Did I need to have bled the heater core? Any suggestions?

probably trapped air.

How do I get rid of the trapped air?

Sounds like maybe some air trapped in the system or may be other i have no experience on it i will just concern to the friend and tell to you.Pull the front tires up onto something taller than the rear and idle it without the cap on for a while...