There's probably been a thread about this but I didn't find it so go ahead and make fun of me and post a link or give some help.
I turn on the heat and it blows cold, not even the defroster is warm. I'm not Farmiliar with this stuff so where do I begin. I did recently replace the thermostat of that helps

 

Can you smell coolant from the vents? Like a sweet maple syrup smell?

 

Either hot coolant from the motor is not sufficiently flowing thru the heater core (under the dash) or the air/heat blend door (under the dash) is not opening/closing properly. Are both heater hoses hot? Gotta have lots of hot coolant for a good heater. If not, suspect a plugged heater core and/or weak water pump....if yes, suspect the blend door. Remote chance it could be both (plugged core/malfunctioning blend door).

 

In class now, will check

 

It sounds like you need to flush and back flush you heater core. Make sure that you back flush it too. Also it can take several flushings to get it clean.

 

What kind of t stat did you put in? Did you have heat before the t stat change?

 

Stock t stat and no I didn't

 

You brought a mopar t stat? Ok we'll that does not matter if you had no heat before you need to flush out your heater core as stated by everyone else... What color is your anti freeze? And does your jeep run at normal operating temp?

 

Flushed it. Works again thanks

 

Good to hear it. I know that I give my Jeep a good cooling system flush every year and I have never had a over heating problem or lack of heat and the heater.

 

Nice thanks for that help