The blend door is a flap in the hvac system that controls whether the air flows through the heater core or the ac evaporator A blend door diagram is a visual representation of a component in a vehicle's heating and cooling system that controls the blend of hot and cold air I too am repairing the hvac air diverting 'stuff' but the heater/defroster flap in my system does not return to the fully up position
1990 Gmc Sierra 1990 GMC Sierra Pictorial Diagram of Heater Core
Is there supposed to be a return spring?
Blend door is to the left of the heater core, you may need to smack your elbow with a 3lb sledge to actually get your whole hand in position, or better, just get someone with smaller hands to fish around.
Gm made minor changes to the hvac over the years, so the controls and door operation vary a little from year to year For each year of truck, there is an hvac control table in the shop manual,. Some of them are very difficult to get to, others are not Either could be your problem
A blend door actuator is a small electric motor in your climate control system that moves the blend door back and forth to control the mix of hot and cold air A blend door diagram shows the location and components of the blend door in your vehicle’s heating and cooling system This diagram can assist you in. In this video, we show you how to reset a blend door actuator step by step
If your car’s ac or heater is stuck on one temperature or won’t switch vents, the actuator may be the problem.
This is the most comprehensive guide to fixing blend doors out there Today i show you exactly how to disassemble the hvac box, clean and recover all the doors, and reseal the box. If your vw doesn't have heat, or ac, odds are the foam on the blend doors has come off I will show you how to reseal the blend doors, to get heat and ac back
Also how to replace the heater core. The blend door mixes the hot air with the cold air in the cabin of your ford truck. Learn what a blend door actuator does, common failure symptoms, how to test it, and how its motor, gears and electronics.
