Hot air mixed with cold blows from air conditioning
When my car has been sitting in the sun and is hot, instead of cold air coming from the air conditioning, I get hot air mixed with the cold from the two side air conditioner registers. When this happens, I have to shut down the two registers and switch on the extra air blower in order to divert the cold air to the center registers. The a/c duct in the back seat has no problem and it produces cold air at all times. I live in a hot climate where we have hot weather year round and I want to bypass all the hot water that goes to the cabin. How can I do this?
Experienced mechanics share their insights in answering this question :
Hey there. You will most likely have to have a mechanic bypass the heater coolant lines to have this resolved. Your A/C may not be controlling the air flow inside the evaporator correctly out of the vents and may be the blend door actuator stuck in the heat position. Have the AC system diagnosed first before bypassing the heater.
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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.
If your air conditioner is blowing out warm air, your unit`s refrigerant levels might be low. This usually indicates a refrigerant leak in your system! If that`s the case, your air conditioner will continue to run and blow out warm air, trying to reach the temperature you set on your thermostat.
Temperature Settings Adjusted Differently for the Passenger and Driver Side. Sometimes the AC blows cold on one side and hot on the other because the settings are set that way. This can be remedied by adjusting the temp on the cold side or vice versa to the preferred degree.
If there isn`t enough coolant in your system, the heater core will blow cold air into your car. Solution: If you confirm that a low coolant level is the source of your problem, you simply need to top off your coolant. You may want to check for leaks as well if you just recently refilled your coolant.
Due to the design of dual AC systems, low refrigerant is the leading cause of drastic temperature difference from one side of the dash to the other. Even well experienced car mechanics may be surprised to learn that as little as 4 to 8 ounces undercharged of 134A can make such a huge difference.
Three of the most common reasons why HVAC systems overheat are clogged air filters, refrigerant leaks, and dirty condenser coils. These issues force your heater or air conditioner to work harder to produce the temperature and quality of airflow you need, which results in the system overheating.
The most common cause of a vehicle`s air conditioner not getting cold enough is that it needs to be recharged. You can recharge your refrigerant by yourself, but to save time and make sure the job is done correctly you should make an appointment with your local professional auto shop.
A car A/C blowing hot air is often the result of a refrigerant leak. Refrigerant is a liquid that circulates through your car`s A/C system, expanding and contracting as it removes heat and humidity from the cabin. None of the other A/C components will function correctly without proper refrigerant levels.
Low refrigerant pressure can cause the left side to blow warmer air than the right side, but in no case will low pressure cause the air on one side to be warmer than the outside air. Your problem is that the left side heater is stuck on.
Low refrigerant pressure can cause the left side to blow warmer air than the right side, but in no case will low pressure cause the air on one side to be warmer than the outside air. Your problem is that the left side heater is stuck on.
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Hot air mixed with cold blows from air conditioning
ANSWER : Hey there. You will most likely have to have a mechanic bypass the heater coolant lines to have this resolved. Your A/C may not be controlling the air flow inside the evaporator correctly out of the vents and may be the blend door actuator stuck in the heat position. Have the AC system diagnosed first before bypassing the heater.
Read Full Q/A … : Hot air mixed with cold blows from air conditioning
My air is blowing cold-hot-cold-hot-cold-hot…
ANSWER : It is possible that you have a leak in the AC system. There are pressure switches that will turn off the compressor if the pressure is too high or too low. The low refrigerant level could cause the AC compressor to cycle on and off. If you would like to have this done, a certified technician from YourMechanic can come to your car’s location to diagnose the AC system and make the correct repair.
Read Full Q/A … : Hot air mixed with cold blows from air conditioning
While driving defroster set to hot blows hot air as it should, while idling it is blowing cold air.
ANSWER : First, the coolant level should be checked to make sure the radiator is full. While the overflow tank may be full, the radiator cap must be taken off to check the level inside the radiator. If you find the level is very low, you have a coolant leak that must be fixed. If coolant levels are normal, an engine thermostat or heater control problem may be what you’re experiencing. Consider hiring an experienced technician like one from YourMechanic who can come out and take a closer look at your lack of heat concern to offer a more personal diagnosis.
Read Full Q/A … : Hot air mixed with cold blows from air conditioning
A question regarding my car blowing intermittently hot and cold air.
ANSWER : It sounds like you have failed cooling fans. When the car is at idle, the fans should run to pull air across the A/C condenser to regulate refrigerant temperatures and the radiator to regulate coolant temperature. If these fans fail, then these components will receive no airflow at idle, but will still get airflow while driving due to the car moving. I would suggest having a qualified technician, such as one from YourMechanic, inspect your fan operation, as well as the rest of the cooling system for proper operation.
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Air conditioning blowing mildly cold air on the coldest setting, turned off/on again, now blowing cold air, should it be checked?
ANSWER : If you are getting ready for a long trip and suspect the cooling fan may be not coming on for the radiator and a/c then you should have the a/c and cooling system performanced checked before trip. Nothing worse than breaking down when out of town in a strange area.
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My 2003 Hyundai air conditioning works fine but often starts blowing hot air, especially when idling.
ANSWER : Hi There,
It sounds like you may have a condenser fan that may not be cooling the AC condenser properly. As you may know, the job of the AC condenser fan is to cool down the AC condenser as it generates a lot of heat during the course of its primary function, which is to convert the AC gas refrigerant into a liquid form, a process that generates a significant amount of heat. As the AC condenser fan blows cool air across the condenser, this allows the condenser to remain cool, keeping the pressure down in the AC system which helps to generate cooler air. I would suggest having a professional from YourMechanic come to your location to take a look at your vehicle.
It sounds like you may have a condenser fan that may not be cooling the AC condenser properly. As you may know, the job of the AC condenser fan is to cool down the AC condenser as it generates a lot of heat during the course of its primary function, which is to convert the AC gas refrigerant into a liquid form, a process that generates a significant amount of heat. As the AC condenser fan blows cool air across the condenser, this allows the condenser to remain cool, keeping the pressure down in the AC system which helps to generate cooler air. I would suggest having a professional from YourMechanic come to your location to take a look at your vehicle.
Read Full Q/A … : Hot air mixed with cold blows from air conditioning
Air conditioning is blowing hot air – car stalls when A/C is on
ANSWER : In order to diagnose all the different problems you have, I having the A/C pressures checked to see if the system is low on refrigerant from a leaking compressor or another component. The rough idle may be due to a dirty throttle body and idle control system. If you would like to have this checked for you, a certified professional from YourMechanic can come to your car’s location to inspect the A/C and rough idle in order to proceed with the proper repairs.
Read Full Q/A … : Hot air mixed with cold blows from air conditioning
Air conditioner blows hot air on the left side and cold air on the right side
ANSWER : A common issue across many makes and models with dual AC in the temperature blend door actuator failing and causing drastic temperature differences between the driver and passengers sides. Have the HVAC system inspected by an experienced professional to find the specific cause. A certified professional from YourMechanic can come to your car’s location to diagnose the AC and assist with proper repairs.
Read Full Q/A … : Hot air mixed with cold blows from air conditioning
