It was narrated from 'Asim bin Laqit bin Sabirah that his father said:
"I said: 'O Messenger of Allah, tell me about Wudu." He said: 'Perform Wudu' well,[1] and exxagerate in sniffing water up into your nose, except when you are fasting.'"[1]See No. 141 (ES)
Arabic/English book reference (ES): Vol. 1, Book 1, Hadith 87 (ES)