Ac blows warm unless in motion
when I'm sitting at a light or in park the AC blows warmer but when I am driving and RPMs are up then the AC blows cold why would that
Experienced mechanics share their insights in answering this question :
This is because when you are at a stop, there is less air flow across the A/C condenser and engine to cool it down. If you have a condenser that is clogged with bugs and dirt, then clean it out to help. If you feel the A/C is having a problem that is not normal, then have a mechanic inspect the AC system for you and make a diagnosis and repair.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
Blocked or Broken Condenser If the condenser has gone bad, it will not be able to process the freon and produce cool air. A broken condenser might malfunction when there is a cut back in power as when the car is idling or running the AC purely on the battery.
Car AC employs a compressor to produce cold gas, which subsequently cools the air. The engine rotation drives the compressor through a belt. So the compressor will pump quicker as the engine revs faster. When you are idling, the automobile revs slowly, while the compressor works less, resulting in warmer air.
Your Coolant System May Be Airlocked If your heat only works when driving, this can also be caused by air pockets. Air pockets within the cooling system can prevent adequate coolant circulation and are sometimes the result of low coolant or a faulty radiator cap.
One of the most common causes of the symptom you`re describing is when you have a bad or failing AC high pressure hose. The high pressure hose is designed to increase and decrease AC pressure during different driving conditions, since the AC drive belt will increase in speed as the vehicle accelerates.
If your A/C flip-flops from hot to cold and back again, your expansion valve could be failing. The expansion valve removes pressure from liquid refrigerant to allow expansion from a liquid to a vapor state in the evaporator. If the valve is blocked, the refrigerant flow could be restricted or could be too unrestricted.
Your car air conditioning works much better when you`re actually driving because the faster the engine turns, the faster the AC compressor runs, which lets the system cool more effectively. Don`t waste time and gas by letting your car run before you go.
If the a/c isn`t blowing cold air when the car is idling, this is an indication that there may be a problem with the AC system high pressure hose. It is also possible that there is a problem with the AC compressor.
Any time you are having an issue with heating and cooling units, such as after a sudden power failure or after your children have had `control` of the system while you`ve been away, resetting the thermostat should be the first thing you try when attempting to rectify HVAC system issues.
If your air conditioning unit has stopped working, there are many possible reasons that can explain why. It could be your thermostat, your air filter, a problem with the condenser or compressor, or it may just be time to replace the unit, especially if it`s over 10 years old.
Check Your Thermostat
First and foremost, examine your thermostat. When an air conditioning stops blowing cold air, it`s typically because the thermostat is set incorrectly or was altered. Children often play with thermostats they can reach. If this is the case, simply reset your device.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
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.
Air conditioner blowing warm air. Heat blowing warm air. Neither hot or cold
ANSWER : If the A/C system is full and pressures are reading correctly, and the cooling system is in proper working order (thermostat opens, no overheating, etc.), then most likely the problem lies with the dash. The climate control head unit may be at fault. One or more blend doors behind the dash may be stuck or broken. If you’re unable to fix this issue yourself, consider YourMechanic, as one of our mobile technician can come diagnose the issue with your A/C firsthand and help you fix it accordingly.
My air conditioner blows warm when idle, looses coolant and starts to overheat.
ANSWER : Hi! I have a couple of thoughts that may help you sort out the issues with your Explorer. There may be separate root causes of the issues with the air conditioning system and the cooling system.
The first thing I would do is a pressure test on the cooling system. This will help to identify whether there are any leaks in the cooling system.
Something as simple as a faulty radiator cap can allow coolant to bubble over out of the radiator. I would just put a new radiator cap on it.
Your engine may actually have a blown head gasket. One of the symptoms can be engine compression leaking into the cooling system and over-pressurizing it to the point of pushing coolant past the radiator cap and out of the overflow. There is a testing tool that can can be helpful called a block tester. It is used to identify the presence of combustion gasses in the cooling system.
A qualified technician from YourMechanic can come to your home or office to inspect your AC system and recommend the best path to repair.
Ac blows warm unless in motion
ANSWER : This is because when you are at a stop, there is less air flow across the A/C condenser and engine to cool it down. If you have a condenser that is clogged with bugs and dirt, then clean it out to help. If you feel the A/C is having a problem that is not normal, then have a mechanic inspect the AC system for you and make a diagnosis and repair.
AC blowing warm air, ac compressor bad?
ANSWER : There are several issues that can cause your A/C to blow warm air. Although the compressor is on that list, one of the most common causes of warm air blowing from the A/C is a bad or failing A/C high pressure hose. The high pressure hose increases and decreases A/C pressure during different driving conditions. If the warm air is coming from A/C vents more frequently when you are at idle, this could be the issue.
There could be other issues that are causing this problem which is why it’s a good idea to have a local ASE certified mechanic help you properly diagnose the problem with your A/C. It will save you a lot of frustration and ensure the A/C is fixed sooner rather than later.
My car AC blows cold air when the car is moving but when I’m at a red right it starts blowing warm air.
ANSWER : When the car is moving, versus stopped, there is more air flow over the condenser (the heat exchanger in front of the radiator) and that airflow is essential to system operation. To maintain airflow when the car is in stop and go traffic, or is completely stopped, condenser fans will come on automatically. If the fans don’t come on, the circumstance you have could occur. You might also have a low state of refrigerant charge. Other possibilities are that the compressor clutch is not cycling as intended or that the condenser might be blocked or dirty. And, of course, you could have a combination of these issues. To get this resolved, the best thing to do is request an air conditioning system inspection. The responding certified mechanic will come to your location, pinpoint the fault and get this resolved for you. Once diagnosed, the mechanic will be in a position to give you a repair strategy to get the A/C system fully functioning and he or she will estimate the cost of the required repair. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
2008 VW Jetta AC not cold
ANSWER : Hi Allen. By far the best way to have your AC system correctly diagnosed is by having an AC inspection completed first. By having one of our professional mobile mechanics come to your location to diagnose the issue correctly, it significantly minimizes the mistakes in completing the wrong service. In your case, the issue could be as simple as needing to have the AC system recharged, or there is an existing leak that needs to be repaired before refilling the refrigerant. Best economic bet is to have the AC inspection completed first.
Ac blows hot in summer heat blows cool in winter
ANSWER : I can understand your confusion and frustration, I believe your Kia is experiencing a few different issues that could all together duplicate the concerns you are experiencing.
It would appear that one or more blend doors, these are inside the dashboard that direct or block fresh air from outside the vehicle entering the cabin, is stuck open. This would explain why you experience cold air in the winter and hot air in the summer. There is a different blend door that will direct or block heat from the heater core inside your dashboard, this door may also be stuck. In regards to the air conditioning, there are a few reasons why it is not working as it is supposed to, however the most common is due to lack of refrigerant.
As you can see, there is a lot going on, therefore I recommend enlisting help of a certified mobile mechanic to stop by and go over your Sedona with you in person and diagnose why you are experiencing these temperature concerns.
