From Hareiz who said: I said to Abu Jafar (as) and Abu Abdillah (as): What breaks the wudhu?
So They (as) both said: Whatever comes out from your two lower ends – from the anus and the glans penis, faeces or urine or semen or fart; and the sleep until the consciousness is gons. All sleep is disliked, except if you happens to hear the sounds.

Imam al Reza (as) was asked about the nose bleeding, whether it break the wudhu or not?
He (as) said: Only three things break the Wudhu – the urine, and the faeces, and the fart.
