Hi all, my heater works beautifully! But too beautifully, I can't turn the heat down. The fan control works perfectly, but the heat won't reduce. I'm wondering if it's the actuator or the heat control ****?

Thanks in advance.

 

While it could be the control, it is more likely the actuator or linkage for the mode door - that is the door inside the box under the dash that controls air from the heater core versus the cooling coils.

The manual for your vehicle is available here:

https://charm.li/Chevy%20Truck/1995/...d%20Diagnosis/

 

Thanks for the info. I'll take a look at the manual and check the actuator first.........I'm guessing that the actuator controls fhe AC as well, which I struggled with and finally gave up.. The rear AC works wonderfully, but I ended up cutting in new vents from the rear to direct cold air above the driver.

 

The mode/blend door would most certainly prevent cold air from coming out the front vents. If the rear AC works, there is nothing likely wrong at all with the front AC - just the mode door is not moving to allow cold air to flow through.

 

so the actuator has been the culprit all along?

 

Most likely. On my 96 C1500, the way you can confirm that is to disconnect the actuator from the linkage, and rotate the shaft that moves the blend door manually, and it should let you shift from heat to cool. I think I said "mode" door earlier, but the mode door is the one that controls if you are blowing to the floor, vents or defroster location. The one you want to look at is the blend door, which controls the mix of hot and cold air.

Newer vehicles like my 2006 which has 2 zones (passenger and driver) are a little more complicated, as there are two blend doors, one for each side of the dash.

 

So the mode door is the one on the left and the blend door, or temp door motor is in the center?

 

If it helps, this diagram on the link I gave you already kinda shows where the TEMPERATURE actuator is. The actuator is the component pointed to by the number 3, and looks to be around the center of the dash. I know the mode actuator is the one on the left, above and to the right of the gas pedal, as I've looked at that one on my 1996 C1500. I *think* there are some linkages to it, but it may just sit over the shaft that moves the door and engage with it directly. I've had issues with MODE on mine (not moving from floor output to vent output), which is the other actuator.

You may need to pull the trim panel and radio to have a clear view of it, if you can't see it from underneath the dash.





Replacement seems pretty simple:

https://charm.li/Chevy%20Truck/1995/...or%20Actuator/

One thing I *HAVE* read somewhere is that you need to maintain the position of the shaft in order to align it and engage with the new actuator when replacing it.

If you determine it is in fact the actuator, Rockauto.com likely has a new one.

 

Yes, and thank you for providing that schematic previously. That's exactly how I'm seeing it.

Take care.

 

OK, circling back on this now that the weather is hot.........

So, the mode actuator on the left appears to be spinning well, but the linkage looks wonky compared to a diagram. The blend actuator in the middle also appears to be spinning well, but temp stays hot when dial is turned to cold. There is another actuator next to the blower that doesn't appear to spin no matter what I activate on the control panel. Is this for the recirc?

Thanks, Ron