He has a Clean Heart but He does not Respect His Parents

Praise be to Allah.

Yes, that is counted as a sin for which a person will be punished, because Allah says (interpretation of the meaning):

“Say not to them a word of disrespect, nor shout at them but address them in terms of honour. And lower unto them the wing of submission and humility through mercy.” [Surah al-Israa’ 17:23-24]

Shaykh Sa’d al-Humayd

Every kind of annoying one's parents, whether in word or deed, is an act of disobedience, which means that the child is a sinner, because it goes against the command and prohibition of Allah, Who has commanded us to speak to them kindly and treat them kindly. Allah says (interpretation of the meaning):

“But address them in terms of honour. And lower unto them the wing of submission and humility through mercy.” [Surah al-Israa’ 17:24]

It is forbidden to dishonour them by saying or doing bad things to them. Allah says (interpretation of the meaning):

“Say not to them a word of disrespect, nor shout at them.” [Surah al-Israa’ 17:23]

If the child does that, then he has to repent to Allah and seek his parents’ forgiveness, so that he may escape the punishment.