Solved Help! No heat. Heater control valve issue.

[Skater388]

My 02 does not have the heat control valve by the heater core. Does it have one? Just replaced the t-stat. Bled the system. No change. One of the hoses going to the heater core is warm, the other cold. Disconnected them and flushed the core Didn't find any obstruction.

Any ideas?

 

[BrooklynBay]

Welcome to this forum! Follow the heater hoses until you see the heater control valve.

 

[Skater388]

Welcome to this forum! Follow the heater hoses until you see the heater control valve.

I have looked everywhere. What side of the engine compartment or is it under the dash?

 

[BrooklynBay]

Look near the passenger's side under the hood.

 

[Skater388]

 

[Skater388]

Thank you for the quick response. I can't find a valve anywhere.

 

[BrooklynBay]

What is the part on the right hose before it goes into the heater core? It looks like it.

 

[Skater388]

That is just a T fitting that is some type of bypass that runs to the drivers side along the firewall.

 

[BrooklynBay]

I think that it's the valve. Is the hose cold on the section closer to the heater core?

 

[Skater388]

Yes!

 

[Skater388]

This just looks like a T fitting to me. Is this it?

 

[gtyates]

Where the "T" fitting is should be the heater control valve. That is where my '05 one is located. Looks like someone removed a bad one and then bypassed it?? That smaller hose coming off of the "T" is for the PCV valve. There should also be a vacuum line that plugs into the heater control valve available. Do you have a small vacuum line in that areas that is capped off? Weird.

 

[Skater388]

I'll have to look for a capped vacuum line. The person I bought the truck from said the heat went out. I don't believ they removed anything. I'll ask.

Thank you again for the help. Great forum!

 

[Skater388]

This is what comes up for my model year. Only shows 2 ports and vacuum operated.

 

[koda2000]

My late production (9/15/01) '01 Sport Trac has what I assume is a vacuum operated heater control valve located sort of under the alternator. When I first got the truck, it had no heat or A/C. I found that the vacuum line that should have been attached to the heater control valve vacuum motor was disconnected and just hanging loose. I reconnected it, but still had no heat. Then I removed and tested the blend door actuator motor and found it to not move when the TEMP knob on the dash was moved. I replaced the blend door actuator and then then the heat worked normally.

The A/C was a separate issue, as the PO had broken the top of the A/C High Pressure switch, near the compressor.

 

[koda2000]

I went out and took a closer look at what I believed to be a heater control valve located under my alternator and that's what it is. No doubt about it. My other Explorers have the valve located in the more common space near the blower motor.

 

[Ngrimm]

There is a module behind the glove box. My heater blew cold until I remembered I had unplugged the connector to the module. I think it controls the blend doors.

 

[Skater388]

I'm on the way to pick one up now. Than you for double checking.

Stay Tuned

 

[Skater388]

All fixed. Nice and toasty.

Thank you everyone for your help!!!!

 

[BrooklynBay]

Thanks for the update! So was it the heater control valve or the blend door? Did you find the valve near the alternator or did you replace the tee with a valve?