However, you might be experiencing a problem with:
* Blend door actuators: These control the direction of the air (face, defrost, floor). If they're malfunctioning, the air might be going where you don't want it, even if the heater is working correctly. This is a very common problem in older Jeeps. A faulty blend door actuator can cause the air to only blow in one direction, regardless of the setting.
* Vacuum lines: The blend doors are often controlled by vacuum. Leaking or disconnected vacuum lines can prevent the blend doors from moving correctly. Check all the vacuum lines related to the HVAC system for cracks, breaks, or loose connections.
* Temperature control cable: The temperature control lever might be connected to a cable that's frayed, broken, or stuck. This would prevent you from properly adjusting the temperature.
* Low coolant: While the heater is working, if the coolant level is low, it might not heat effectively enough. Check your coolant level in the overflow tank.
* Thermostat: A faulty thermostat might be preventing the engine from reaching the proper operating temperature for sufficient heat.
* Airflow obstructions: Leaves, debris, or other obstructions in the air intake or vents might be restricting airflow.
In short, because the heater and defroster *are* working, the problem is almost certainly in the *direction* of airflow or the *temperature* control. Start by checking the simplest things first: coolant level and vacuum lines. If those are good, then suspect a blend door actuator problem. A mechanic or online forums specific to Jeep Cherokees (like CherokeeForum.com) can help you diagnose further.
