One car, two climates: Why Koreans keep fighting over the subway's temperature

Even when the outside temperature is hot and humid in Seoul in July, you'll be welcomed with refreshing, cool and air-conditioned cars once you step inside Seoul's famed subway system. 

Yet people are still complaining about the air conditioning. Look to your left and someone is shivering, texting the authorities to turn off the air conditioner, while others are sweating in the subway — and nobody is winning this war. 

But is anyone actually complaining?

Out of the 1.01 million discomfort complaints filed by commuters and riders of the Seoul Metro last year, around 790,000 complaints, or 78.4 percent, were complaints about the temperature, and most complained about the trains being too hot. Seoul Metro, owned 100 percent by Seoul's local government, is in charge of operating Seoul Subway Line No. 1 to Line No. 8. 

The complaints also come at a similar time, during rush hour. Out of all the "too hot" complaints last year, 72.8 percent arrived during the morning and evening rush, according to data from Seoul Metro in June. So did the cold ones: 57.3 percent of the complaints saying that the carriages are too cold also landed in those same crowded hours. 

Can they not make the trains colder or hotter? 

Even other than the fact that you can't have one carriage be hot and cold at the same time, it's also not really possible for a driver to control the air conditioning like people can do in a car. 

Under a standard set by the Ministry of Climate, Energy and Environment, subway cars are cooled automatically to 24 degrees celcius (75 degrees Fahrenheit) in the summer and 18 degrees celcius in the winter. A crew cannot "power-cool" a single carriage, per se. 

And it's not like anyone is completely wrong — the temperature inside one car can be uneven. Often, the middle of the train will run hotter than the areas at the ends of the carriage, according to Seoul Metro, due to the airflow. Other factors, such as how full the carriages are and whether the passenger is seated or is standing right underneath the air conditioning unit, all factor into how two people in the same carriage might feel differently. 

How is Seoul Metro responding? 

Seoul Metro's response, for now, is mostly information and nudges. It put up stickers explaining how the heating and cooling work on lines No. 2 and 8 last year, with line No. 6 added this year. The stickers explain that the heating and air conditioning on the train are set automatically to the threshold.

Seoul Metro also posted a notice on its Ttota complaint app warning that a flood of temperature reports ties up staff who might otherwise be answering emergencies. 

What can a rider do? 

Riders still have options of their own. Those who find the temperatures in the subway cold can — other than bringing extra layers — move to carriages with warmer temperatures. The cars are labeled with a "weak air conditioning" sticker and are kept 1 degree Celcius warmer than the rest. The fourth and seventh carriages feature weaker cooling on lines No. 1, 3 and 4, the fourth and fifth on lines No. 5, 6 and 7, and the third and fourth on line No. 8.

Airport Express line, Bundang line and the DX Line — commonly known as the Shinbundang line — all have one carriage dedicated to weaker air conditioning. 

Line No. 2 and Line No. 9, often touted as the most crowded lines, however, have none. 

"Train temperature is automatically controlled to a government standard, and every department is doing its best to make the ride comfortable," Seoul Metro said. "Because our crews cannot adjust the cooling at will, we ask riders to understand and cooperate so that urgent reports such as medical emergencies and crimes can be handled first."

BY CHO YONG-JUN [[email protected]]