Heater Problems

[buddy]

I HAVE A 2002 Expedition XLT 4.6. The heater only blows warm air out both front and back. Put on new thermostat but didn't help. Man at parts store said try a Heater Valve. Any thoughts on trying this? I will say that the air conditioner only gets cool in hot summer if this is any help to anyone looking at this. IT'S COLD HERE!!!!!! I have looked all over this site and didn't see anything that would help. Thanks

Buddy


If it's the heater control valve ( where is it located? )

 

[stamp11127]

There are numerous threads on here about little or no heat.
First you should establish that you have coolant flow in and out of the heater core. With the engine at operating temp grab onto both heater hoses. Both should be hot.
If one is hot and the other isn't, the heater core is partially blocked or there is a flow problem from the engine.

 

[buddy]

Yes, they are both hot and I have looked at other threads on here.

 

[stamp11127]

Good that both lines are hot.
The next thing to check is the blend door operation. The bottom part of the blend door can crack/break or the blend door actuator can fail.

 

[phase_one]

Where is the blend door? Yes Im new to this vehicle. Thanks for the help

 

[Bedrck47]

there is no heater control valve on the 1st gen expy's

blend door is located in the chamber behind the glove box There are plenty of threads on the forum about the blend door and also good videos on youtube