Breathing issue. Is just 32 months old.

Though my daughter is healthy and active. But her nose blocks at night even in summers. And i started putting her in another room to avoid air conditioner. But even when fan blows, her nose is blocked. And while i keep the fan off. She sleeps well and her breathing is good. This problem is gone in morning hours. I just keep AC in another room and fan in the room where we sleep. My fan room has a same entry with AC room. A nd the room only gets to 28 degrees even with AC on in the another room. While i use EASIBREATHE capsules ok her clothes. She is ok. And secondly when she coughs sometimes her cough sounds like watery. I mean its not dry cough. Please suggest how to tackle her problem. She is just 32 months old.