Heater control valve problem?

[jimbo231]

I had the heater control valve replaced last year on my 1998 explorer. Ever since I have had no heat. The heater hoses are both the same temp so I don't think the heater core is plugged. When I turn on the heat there is no vacuum an the plunger stays out on the valve. When I turn on the air conditioning , vacuum is applied to the valve sucking the plunger in. I was just wondering if that is normal or backwards? Also does it matter how the two hoses going in and out are connected or can the be connected wrong?

 

[Maniak]

The hose from the intake manifold goes to the "in" side of the heater control valve and the "out" side of the valve goes to the water pump..

On the heater core side of the heater control valve it doesn't matter.

~Mark

 

[jimbo231]

So it's marked "in" and "out" on the valve? Does the way the vacuum operates on mine seem right? The A/C applys vacuum and engages the plunger.

 

[Maniak]

At least the heater control valve I got was.. Actually, now that I think about it, the last one wasn't.. but it did have an arrow to show the direction the fluid should go...

And yes, when you put the system on max a/c (might just be a/c on your X) the valve should move to the hot water never goes into the heater core.

~Mark