2008 ranger blend door not working

Are the heater hose from the engine compartment going to the fire wall hot to the touch ? Is the HVAC - heating , ventilation an A/C system manual or automatic ?
Control System Inputs-Manual A/C
Climate Control Assembly
The climate control assembly has three system controls:

• The A/C heater function selector switch combines a vacuum selector valve with two electrical switches to supply battery voltage (B+) to the A/C clutch circuit and the blower motor speed control circuit.
• Temperature selection is accomplished with a potentiometer connected to the electric blend door. Movement of the control knob from COOL (Blue) to WARM (Red) causes a corresponding movement on the air temperature blend door and determines the temperature that the system will maintain.
• The blower motor switch controls blower motor speed by adding or bypassing resistors in the heater blower motor switch resistor.

Control System Outputs-EATC
A/C Blower Motor Speed Control
The A/C blower motor speed control is located on the A/C evaporator housing, in the engine compartment.

• The function of the A/C blower motor speed control is to convert low power signals from the electronic automatic temperature control module to a high current, variable ground feed for the blower motor.
• Blower motor speed is infinitely variable and is controlled by the electronic automatic temperature control module software.
• A delay function provides a gradual increase or decrease in blower motor speed under all conditions.

A/C Electronic Blend Door Actuator
The A/C electronic blend door actuator is located on the top of the plenum housing.

• Its function is to move the air temperature blend door on command from the control assembly.
• The A/C electronic blend door actuator contains a reversible electric motor and a potentiometer. The potentiometer wiper is connected to the actuator output shaft and moves with the output shaft to indicate the position of the air temperature blend door.
• A 5 volt signal is applied to the ends of the potentiometer. The voltage available at the wiper indicates the position of the potentiometer. The expressed value of the actuator wiper voltage is sent to the electronic automatic temperature control module and is matched with the wiper voltage of the module potentiometer. The control module then drives the actuator motor in the direction necessary to make the actuator wiper voltage agree with the control module wiper voltage.

Could be the blend door is not opening/uncovering the heater core to let the heat in. Most likely is the problem. You need to be sure that actuator motor is working to open the main blend door. It's vacuum actuated so be sure your getting vacuum to all the connections and lines from the engine to the actuators.

If you are looking for some sort of water valve that diverts water to/from the heater core, forget it. They don't exist anymore. They went away shortly after the widely adapted use of air conditioning in today's modern cars. Now, hot coolant is routed thru the heater core at all times, but is controlled by a cable-operated, or vacuum operated "blend door" located inside the heater box. If you are not getting heat to the vehicle, there are a few possible problems:

1. Bad thermostat - thus low coolant temperature and lack of heat.
2. Clogged heater core - no water flow thru core, thus no heat.
3. Broken control head - loss of cable or vacuum actuation of blend door.
4. Broken heater box/vacuum tank - no actuation of blend door.

Of the items listed above, based on the age of the vehicle and the likelihood of occurrence, I would investigate them in the order of 2, 4, 1, 3.

Do you have Manual Climate Control System or Dual Automatic Temperature Control System ?
The temperature control switch:

• is a potentiometer that outputs a variable voltage to the temperature blend door actuator to set the position of the temperature blend door.
• initiates closing of the heater control valve. When set to full COOL, a lever on the temperature blend door pivot shaft depresses the pintle of the heater control valve vacuum switch. The heater control valve vacuum switch then applies vacuum to the heater control valve, closing off engine coolant flow to the heater core.
• is serviced only with the climate control assembly.

You may have disturbed something when changing the actuator , the vacuum switch o vacuum hose .

here's a few things (1) is the thermostat facing the right way /the arrow head facing out towards the front of the car or facing up towards the hood ? the blend door actuator/the a/c vacuum control valve/ or vacuum lines can be broken connected wrong or missing altogether here's some pictures for you
this is a blend door actuator

I don't know which one you have or both

a/c vacuum control valve

this is the blower motor resistor I really don't think so on this one because the fan blower works ,so concentrate on vacuum lines and the vacuum controls here and you should be warm soon good luck

The most common cause of this in the Ranger and the Explorer is that a part called the air temeperature control blend door acuator or the blend door shaft that the electric actuator moves has broken, this door is what shuttles between the heater core and the AC core and provides either heated or cooled air, or a blend of the two hot and cold air streams.

hi Planeman.
Why is the heater in my car not working? Ken Mattson, owner of Len's Automotive in Bellevue, Wash., says a car heater can stop working for a number of reasons, including: A low antifreeze/water level in the radiator due to a leak in the cooling system. A bad thermostat that isn't allowing the engine to properly warm up.11 Dec 2013

Why Isn't My Car Heater Working? ' Angie's List

https://www.angieslist.com/articles/why-isnt-my-car-heater-working.htm Search for: Why is the heater in my car not working?
Why is my car heater not blowing hot air?Hot coolant from the engine passes through a heater core, which looks and functions a lot like a small radiator, and a blower motor forces air through it. ... It's also the reason that a plugged heater core, stuck thermostat, or air in the cooling system can all cause a car's heater to blow cold.9 Jul 2017When Your Car Heater Blows Cold Air - Lifewirehttps://www.lifewire.com/when-your-heater-blows-cold-air-534667
How do you fix the heat in your car?Begin with the vehicle on level ground, engine off (cold) in park with the emergency brake set.Heater Controls. Step 1 - A heater cannot operate unless the engine is full of coolant/antifreeze. ...Refilling Cooling System. ...Engine Thermostat. ...Blend Door Actuator. ...Broken Vacuum Line. ...Heater Control Valve. ...Vacuum Gauge. ...Heater Core.How to Fix a Car Heater in Under 30 Minutes - 2CarPros
What are the symptoms of a bad thermostat?A motor with a bad thermostat will run fine for the first few minutes, then overheatrapidly. Other symptoms include the engine and radiator making a rumbling, gurgling, boiling sound: like a steam pipe knock, if you've ever heard one of those. A thermostat sticking open can make your heater not work in the winter.Auto, Car, Truck THERMOSTAT Repair bad thermostat symptoms
or go to this link if you need more help.
2008 ford ranger has heater that won get hot Google Search

sound like a vacuum leak. you can check this by spraying wd40 very carefilly on the vacuum lines under the hood. the idle will change when a leak is detected. could also be a modulator valve or vacuum line under the dash. check this with a spray bottle filled with water. dont want the smell of wd40 in the cabin

you have to replace the blend (heat/cold) door motor, you can try to remove motor and turn door and try to jam something in door handle slot ,that the part that the motor turns,hope this helps.

Is the heater working? Turn the A.C. off with the car at an idle. Turn the A.C. on and listen for the compressor to turn on. (should hear a click under the hood and the motor should change pitch. If no noise, the compressor is not comming on. The o-rings were bad about leaking on these cars, letting out all the freeon. If there is no freeon, the low pressure switch won't let the compressor run.