Most likely, the motor fans on the bottom have gone out. You should buy a fan base or get it repaired soon. Otherwise, you'll damage the laptop from overheating.
Why my Laptop is becoming so hot? I am using HP 430. Please help me.
There may be problem with your CPU or Hard disc. If CPU is getting Too Hot this problem can arise or if your hard disk is having problem then this problem occurs. Get it to Technical person if you can not solve it.