For people using translation apps, it's probably going to translate incorrectly. The sign says "냉난방 중". Bang(방) can mean room (seems a lot of ppl in comments are translating it this way) but in this case they're referencing naengbang(냉방) and nanbang(난방) (cooling and heating). 중 is like a state of being, or when someone does something. which i believe is them saying someone who is hot and cold, someone with big personality changes and they're saying Chan has the biggest difference of the members. He is warm hearted but can be colder/cooler when working on songs. Sorry if any of this is translated wrong, but I believe that's the concept they are going for here.
They were talking about The difference between broadcasting and real life main characters... That's why Hyunjin gives an example to it at 2:34.. Sorry for my englisheu... 😂
Here is rough translation for what BangChan said 2:45 BC: my name is BangChan. It's not because the room is full. LN: BangChan because the room is full? Aa.. Sub: i have a lot to say, but i won't I was also confused, let's wait for the eng sub
Leeknow said "Is it Bang(means 'the room' in Korean) Chan(means being cold in Korean, adjective) because the room is cold?" ('냉난방' means air conditioning and heating,, it is just pun
I think what Seungnim means is that he is very strict leader but he loves the boys on and off camera. But he is also a different person when he's in the job and when he's not in the job.