Heater heating but not correctly

[kardez]

I had a new waterpump and thermostat installed in my 05 Yukon XL and since then the heater does not heat up blazing hot. I am about 90% sure that the heater hoses are crossed at the heater core from what I can see in diagrams I have looked at online. I'm looking for confirmation on what the inlets and outlets are on the waterpump and heater core to confirm what the right flow direction is. Thanks

 

[Eric70]

Did you get this figured out?

 

[SLCHOE]

If this helps you Eric:

The one more forward towards the radiator goes on the most passenger side of the heater core.

It really doesn't matter though. You can route them either way. More than likely there is air in the system via a leak and not enough coolant is flowing through the heater core which is a high place in the cooling system.

 

[kardez]

Thanks for the help. It was a simple fix... just had the system flushed.