6 common reasons why air conditioners blow out hot air.
(Baonghean.vn) - During use, air conditioners often encounter problems such as excessive noise, poor cooling, water leaks, etc. Among these, the air conditioner blowing out hot air is a fairly common problem. So, what are the causes and how to fix this "problem"?
1. Incorrect fan speed setting selected.
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The air conditioner suddenly starts blowing out hot air, while the cold air disappears without a trace – this could be due to accidentally selecting the fan-only mode.
Air conditioner remotes usually have modes such as Dry (dehumidification), Cool (cooling), and Fan. Normally, to cool a room, you should always use the Cool mode, but if you accidentally select the Fan mode, the air conditioner will only blow out hot air or only the fan will operate.
In this case, the solution is very simple: just use the remote control to switch the mode to Fan Cool, and the air conditioner will immediately blow out cool air.
2. The filter is clogged with too much dust and dirt.
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If the air conditioner is only blowing hot air, it could be because the indoor unit's filter is clogged with too much dust and dirt; the cold air cannot escape and gets trapped in the ducts, forming ice.
To resolve this issue, the filter should be carefully removed and cleaned, then the machine should be turned on in fan mode to allow the ice to melt gradually. Once the ice has melted, the machine will operate and blow out cold air as usual. If the filter is too old, it needs to be replaced.
One thing to note is that when using an air conditioner, remember to clean it regularly to avoid encountering the situation where the air conditioner only blows out hot air and not cold air, as mentioned above.
3. The engine block is damaged.
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The compressor is considered the "heart" of an air conditioner. Therefore, when the compressor fails, the gas exchange process stops, leaving only the indoor unit fan spinning and blowing out hot air.
There are many signs to detect a malfunctioning engine, such as noisy operation, unstable temperature, hot air emission, and the condenser unit constantly shutting off.
4. Gas-free engine
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During the use of an air conditioner, the amount of refrigerant gas will decrease, causing the cooling capacity of the air conditioner to decrease accordingly; when the gas runs out, the machine will no longer blow out cold air.
Normally, air conditioners rarely run out of refrigerant, except in cases of gas leaks.
Therefore, when your air conditioner blows out hot air, you should call an air conditioner technician to check for and fix any gas leaks.
5. The machine's fuse is blown.
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With prolonged use,The fuses on the filters may come loose; you need to unplug the machine and check if the fuses are still usable. The machine's fuse is a small silver plate located inside the machine. If it's not working, it needs to be replaced.
6. The gas pipeline is frozen.
If your air conditioner is blowing hot air, it could be due to a malfunction inside the unit. In this case, open the indoor unit and use a flashlight to inspect the inside. Touch the air ducts with your finger; if they feel cold, it means they are frozen.
In this situation, you should turn on the machine in fan mode to melt the ice, combined with opening the window (or door) to allow fresh air in, which will help the ice in the pipes melt faster.