Not only was I sweating like rain, but after turning on the central air conditioner, I noticed a significant difference in the temperature at the upper and lower vents.
The essence of this kind of ice and fire situation is that when the air conditioner is turned on, the warm air intake valve is opened/not completely closed, causing warm air to flow in. Common fault points mostly occur in components such as heating air inlet valves and modules.
Common causes of car air conditioner failure: warm air comes out on the left side and cold air comes out on the right side:
The situation that causes warm air to come out at the same time and cold air to come out from the vents is usually caused by the hot and cold separation partition. Caused by not closing tightly.
1. The temperature setting is high on one side and low on the other;
Dual-zone central air-conditioning means that both the main cab and the co-pilot must adjust the temperature. If one side is low, it may cause the other side to become hot. One side is cold.
2. The heating and cooling knobs are not adjusted properly;
For example, when you think of warm air, the knob is not adjusted to bright red, or when you think of air conditioning, the knob is not adjusted to dark blue.
3. Insufficient refrigerant or too much refrigerant
4. The warm water inlet valve is blocked;
The fully automatic system zoned central air conditioner has two water pipes. In the warm water storage tank, if one block is blocked and the other is not blocked, the upper and lower temperatures will be different, and the temperature of the air inlet will also be different.
5. The servo motor is damaged.
6. A malfunction occurs in the air-conditioning computer, which will cause the air-conditioning hot and cold pipe valve to fail. You can reset the computer and try again.
7. The output power of the refrigeration compressor is low and the working pressure is abnormal.
The basic idea of ??the car air conditioner is that warm air comes out from the left side and cold air comes out from the right side:
While checking for faults in the air inlet valve, you should also pay attention to whether the warm air inlet valve is faulty. Can work normally.
For automatic central air-conditioning, you should also consider whether there is a fault in the central air-conditioning module part (although the probability is small, it cannot be ignored).
Common troubleshooting examples of car air conditioners with warm air coming out from the left and air conditioning coming out from the right. Beijing Hyundai Tucson air conditioner vent blows warm air sometimes and cold air sometimes
Common fault description:
Car series: Beijing Hyundai Tucson 27LSUV produced in 2009, with a driving mileage of more than 70,000 kilometers, and equipped with automatic central air conditioning.
Status:
According to customer reports, the air conditioner is blowing on while the car is driving, and the vents blow warm air and cold air sometimes with no special regularity. This common fault sometimes occurs several times a day, and sometimes it does not occur.
Plan: This car has been repaired several times due to this fault, the refrigerant has been added twice, the air-conditioning evaporator temperature sensor has been replaced, and the air-conditioning module has been replaced with other cars. But common faults cannot be solved from beginning to end. Regarding the user's description, the editor thinks that one thing may be inaccurate, that is, the vents will not blow out warm air. The user's description should be the air blown out of the vents after the compressor stops working. There is also a possibility that the wind power setting is too low and the surface temperature sensor of the air conditioner evaporator reaches the lowest temperature. The compressor shuts down normally.
Based on the editor's basic analysis, the user said that when the air conditioner is not working, it is different from the normal air conditioner shutdown, so it is a common fault of the compressor shutting down intermittently while driving. Press and hold the A/C power switch at idle speed, adjust the wind speed to a higher gear, and use a barometer to check that the low voltage of the air conditioning unit is 285kPa and the high pressure is about 1705kPa, which basically meets the required working pressure.
The air-conditioning unit has no fault code stored, and the air-conditioning unit works normally when it is stationary and waiting for speed. A road test was carried out, the temperature was set at the lowest temperature of 17.5°C, and the wind speed was set at fast gear. No common faults occurred after about 2 hours on the road. The editor once again asked the customer to recall the situation when the fault occurred. Is there any other symptom that can give clues? After thinking about it for a while, the customer told me that when there was no air conditioner blowing out from the air vent, he felt the refrigerant temperature indicator. It's a bit high, but it doesn't reach the red area. Since each time it lasts is not very long, I don't care too much. From what the customer said, the maintenance idea seems to be clear. The intermittent non-working of the air conditioner while the car is driving is probably related to the high engine temperature.
So the engine's refrigeration system was checked to see that there was sufficient refrigerant, and the refrigeration fan started and stopped as the engine temperature increased and decreased, and there was no abnormality. Based on past experience, the probability of identifying a problem with the water temperature sensor is relatively high, because if the water temperature sensor does not turn on directly according to the designed temperature, the engine's refrigeration system will not be able to circulate immediately, and the engine may suddenly fail. High temperature, the car engine control module will cause the air conditioning unit to stop working. When the water temperature sensor opens slowly, the refrigerant enters the general circulation system, the engine temperature drops to the normal range, and the air conditioner will resume work.
After replacing the water temperature sensor, we conducted a follow-up phone call with the customer to confirm that the common fault of intermittent shutdown of the central air conditioner had not occurred again.