New heater core...now no heat

[John Gilbert]

Originally Posted by John Gilbert

Bleed the heater hoses. Its kind of like bleeding the air out of brakes. Its been an awful long time since I bled a heater, but as I remember it you crack the top hose loose while its running and let it flow until there's a steady stream of water.

And if you don't have water flowing through the loose hose, there's no doubt you have a bad heater control valve.

Also, too low a thermostat will effect heater output. like a 160, or a 180 or none at all.