AC will only blow air on defrost and not on vent.
AC only blows out on defrost. It wont blow air on vent or feet.
My car has 96000 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hello, on this particular model of vehicle they have whats called a blend door actuator in the HVAC unit under the dash. If it doesn’t switch from defrost to front air, this is probably your issue. This repair is very similar to replacing the HVAC blower motor and probably close to the same cost. If you would like to have this repair taken care of, a qualified professional from YourMechanic can come to your car’s location to perform this service.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
Bad Mode Door Actuator
The first cause of AC only blows through defrost vents issue is a faulty door actuator. The function of the mode door actuator is to control the vents to ensure that air will be blown out properly according to the custom settings.
If you can hear the blower motor but no air comes from the vents, check the fresh air intake. If it`s plugged, clean it. If it isn`t, the blend door may be stuck, or the vents may be plugged internally. Check for power at the blower motor.
One of the simplest reasons your AC is only working in certain rooms is vent obstructions. This issue can take three different forms: Closed vents: As you might expect, air can`t blow through a closed vent. Check the settings on your vents to ensure they are not preventing air from being released into your room.
Check the vacuum hose on the blend door and see if it has came off or broke. For the rear defroster, check the switch to the defroster and make sure that it has power to it and power coming out. If there is no power to the switch, then check the fuses and see if any of them are blown.
The big surprise about defrosters is the system that drives it… the air conditioner. It is your air conditioner that helps to get the moisture out of the air (and off the windshield). When you turn the defrost on, it`s your air conditioner that kicks in to help get all that moisture out.
Sadly, during the defrost mode the air conditioner will stop blowing hot air. In-fact, it may blow cold air. The main thing for the user is to not panic, leave the system on and do not adjust the temperature, fan speed, zones or operating mode.
Mode Door Actuators: The mode door actuator controls what vents have air flow, i.e. floor, panel or front, defrost, or any combination of those.
If your air handler is running but not blowing air, there are two likely scenarios; either a broken AC blower belt or an issue with the motor itself. If the air handler is humming or buzzing, but not making the mechanical sounds of a motor running, you`re most likely talking about an issue with the motor itself.
Why Is My Central AC Running But Not Blowing Air? If you can hear the unit running but you feel no air (or a minimal amount of airflow) from the vents, there is likely a fan-related issue. Often what we see in this situation is that the fan capacitor has stopped running altogether and it needs to be replaced.
To clean a clogged expansion valve, you will need to access the evaporator coils. Once you have located the coils, use a brush or vac to remove any debris that may be blocking the valve. With the valve clear, the system should be able to function properly once again.
Your defroster (in addition to drying the humidity from the air) is also equalizing the temperature of the glass and the interior air to some extent. Unfortunately, this also means that if your air conditioner isn`t working properly, your front defroster won`t work right either.
It can take up to an 1 hour or 24 hours to unfreeze your air conditioner. It all depends on the extent of the ice buildup. As you`re waiting for the unit to thaw, you should keep an eye out for: An overflowing drain pan.
First, turn the heat on its maximum setting because hot air can hold more moisture. Then, turn the AC on, which will pull the moisture from the air as it passes over the cooling coils. Finally, turn off the recirculation button so colder, dryer air is brought into the car.
The entire system is reversed as the air conditioning is turned on, which causes the refrigerant to heat up and run through the outdoor coil to melt ice. The outdoor fan is stopped to prevent it from cooling the outside coil. The defrost will continue until the temperature of the outside coil reaches about 57 degrees.
Power is routed through the defrost termination switch (thermostat) to the heater. The defrost termination switch (thermostat) is mounted to the coil at the top. The defrost termination switch (thermostat) will cycle power to the heater off and on for the duration of the defrost cycle.
If a duct is blocked, some rooms won`t heat or cool the way they`re supposed to. Because the rooms can`t reach the temperature you`ve set on your thermostat, your HVAC system will be working constantly to keep up.
There are several methods we can use to remove ice from evaporator coils and the three most common are air defrost, electric defrost, and hot gas defrost.
It is the job of the AC actuator to control the opening and closing of the airflow in response to the thermostat, thus controlling air movement and allowing cool air to blow down the ducts and into the house. The AC actuator is located above or below the coil. It can be set to either single speed or variable speed.
If there is no air coming from your vent/s but the system is running, this usually means something has blocked the duct so no air can get through to the vent. Solution: Call an air conditioning service technician to unblock the duct and to make sure all systems are working correctly.
Ice on the AC unit typically means that your system has one or both of these two problems: There is not enough airflow entering your AC system. There is a leak in the evaporator coil or refrigerant lines.
The leading cause of a frozen HVAC system is a dirty air filter. The air filter cleans the air circulated into your home. As your AC system runs throughout the summer, the filter catches dirt, pollen, dust, and other allergens. This can restrict airflow and could lead the HVAC coils to freeze.
Reasons for weak AC airflow include: A clogged air filter. Frozen evaporator coils. Leaky or blocked air ducts.
Problems like a fan clogged with dirt, a dead motor, a loose fan belt or a stuck wheel can all cause your blower to not work properly. These problems can keep the blower fan from blowing enough air out of your vents to keep you cool. Your evaporator coil needs air to blow over it to complete your AC`s cooling process.
Generally, a unit must run for a minimum of about 35 minutes after starting up before completing its first defrost. From there, defrosts should occur no more often than approximately every 40 minutes.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Problem with AC/heater – 2005 Ford Explorer
ANSWER : Hello. The problems you describe with the front system may either be a faulty control switch or faulty vacuum motors for the air blend doors. The problem in the rear is likely the rear heater control valve, which regulates the flow of hot coolant to the rear heater core and air duct system. The clicking noise may be a broken vacuum motor for that valve (integrated in the valve).
I would recommend having a certified mechanic, such as one from YourMechanic, come to your location to perform an inspection of the heater and suggest the needed repairs.
Read Full Q/A … : AC will only blow air on defrost and not on vent.
air conditioner not blowing air from dash vents, but blowing air from side vents
ANSWER : A few different items can cause the air to not blow out of the dash vents. The most common are a blend door or a control switch. The best method for the AC diagnosis feature can be found in the vehicles owners manual. I recommend having your AC checked by a qualified technician, such as one from YourMechanic, to have the problem diagnosed and repaired correctly.
Read Full Q/A … : AC will only blow air on defrost and not on vent.
My heater is blowing air through the driver side air vents but is blowing cold air through the passenger side and rear console ven
ANSWER : Hi there:
Climate controlled vehicles have multiple electrical relays that open and close vents to maintain the desired temperature. In some instances, these relays can wear out overtime. However, it’s also common for debris to clog up vents (especially side vents) which may restrict the flow of cool air. The best way to determine why your AC is not working efficiently, it might be best to have a professional mechanic complete a AC inspection; so they can pinpoint the source of your issues and recommend the right repairs.
Read Full Q/A … : AC will only blow air on defrost and not on vent.
everytime I turn my car on the ac starts to blow air even if I switch it off. it won’t blow cold air or heat.
ANSWER : Hi there. Based on your question and input, it looks like your AC control switches are damaged, causing the vents to activate even if the switch is not activated. This is sometimes an electrical problem, as it could be triggered by a damaged electrical relay. You might want to have a professional mechanic complete an AC is not working inspection, so they can determine what is causing this issue you’re experiencing and recommend the right repair.
Read Full Q/A … : AC will only blow air on defrost and not on vent.
I have a 1999 chevy Tahoe that only blow air from the defrost vents. How can I get the air to blow in your face of feet?
ANSWER : The control actuator that moves the door to control this may have a wiring connector issue due to connections at control head and actuator wiring was miss routed and it pulls the harness connector wires too taught. You should disconnect and reroute the harness to not be too taught and do a drag test and pin connector test to make sure harness connectors are good. You may need to repair one or more connector female pins. If after repairs the actuator may need to be replaced.
Read Full Q/A … : AC will only blow air on defrost and not on vent.
My ac only blows through defrost vents
ANSWER : Hello. From the symptoms you’ve described it would appear to me that the vehicle may have more than one problem.
The hissing coming from the AC condenser may be a sign of a potential leak, especially if it occurred after you added refrigerant. I’d check to make sure the refrigerant is at the correct level and that there are no leaks present, as any AC refrigerant leaks can cause problems with the functionality of the AC system.
In regards to the air only blowing from your defroster vents, I would check the vehicle’s AC mode switches, and blend door actuator to make sure they are operating soundly. The AC switch controls the modes that the AC blows through, so any issue with the switch may cause problems with what vents the system can operate from.
The blend door actuator is the component that mechanically selects what vents the AC system works through, and if it fails or gets stuck, can produce the symptoms you are experiencing.
If you need assistance with these checks, see the help from a certified mechanic who can diagnose your AC issue firsthand and fix it accordingly.
Read Full Q/A … : AC will only blow air on defrost and not on vent.
Overheats When Blowing Warm With Heat & AC But Not When Blowing Cold AC
ANSWER : Hello, thank you for writing in. There are so many different codes being triggered, that it is unlikely all of these systems are having issues at once. We need to focus in on the fact the engine is overheating at all. You will want to check the level and condition of the coolant and the overflow tank. If the level is full then you may have an issue with the thermostat, radiator cap, or water pump. These can all be tested and changed relatively easily. If the main cooling system is okay, you will want to look into the heater core and climate control module. For more diagnostic help, contact our service department to schedule an appointment.
Read Full Q/A … : AC will only blow air on defrost and not on vent.
Ac compressor. Blowing hot air through front vents and cold air through rear vents.
ANSWER : It sounds to me like you have a blend door actuator problem. The blend door actuator is responsible for controlling the blend door. The blend door is responsible for blocking off air to the heater core when your air conditioning is on. I would recommend having your blend door actuator tested using the manufacturer’s recommended procedure. Once this has been done, a qualified mechanic will be able to inform you of whether the actuator will require replacement in order to resolve this issue. If you need help with this repair, YourMechanic offers a repair and diagnosis service preformed by a certified mechanic that will commute to your location to look inspect your heater and AC problem.
Read Full Q/A … : AC will only blow air on defrost and not on vent.
