Troubleshooting car problems of heater without blowing hot air
When your car is quipped with the standard heater system or if it is not equipped with an automatic temperature control system, this kind of problem is an indication of a heater control valve that is not opening. A standard car heater operates using a heater core similar to a small radiator that is located behind the dashboard. The purpose of heater core is to emit heat because of the hot coolant that circulates around the core. The heat that emits by the heater core is then blows by a fan out of your car a/c vents into the passenger compartments.
The heater control valve is the one that controls the flow of the coolant into the heater core. When the valve is open the coolant will flow into the core making the fan to blow hot air into the passenger compartment. Now, when the heater valve is closed the coolant will not flow into the heater core resulting from blowing of air that is not hot out the a/c vents. Since the problem is a heater that is not blowing hot air inside your car passenger compartments then it’s obvious that the heater control valve is not opening.
Possible Cause Why a Heater is Not Blowing Hot Air
The heater control valve is not opening.
How to fix car heater not blowing hot air
Bring your car to a reputable auto repair shop that is specialized in heater repair and ask the mechanic to inspect the heater control valve as well as the device that controls the opening and closing of the valve and repair if necessary. After the repair the mechanic might tell you to replace the heater core also to improve heater performance. However, replacing the heater core will not contribute that much in improving the heater performance, by just repairing the heater control valve will do in improving the performance of your car heater that is not blowing hot air.