Is it disliked to perform ablution (Wudu) with heated water?
Chapter on what purification is achieved with regarding water
Al-Mughni
Book of Purification
Primary text
It is not disliked to perform Wudu with water heated by a pure source. However, if the heat prevents the complete washing (isbagh) of the limbs, it is prohibited. This ruling is supported by the practice reported from Umar, his son, Ibn Abbas, and Anas (may Allah be pleased with them). The scholars of Hijaz and Iraq unanimously hold this view. Evidence includes the narration that Umar possessed a container in which he heated water, and the action of Ibn Abbas, who entered a bathhouse in Juhfah. Furthermore, a narration from Shuraik concerning the Prophet's camel groom states that after becoming ritually impure while traveling with the Prophet, he heated water for Ghusl and the Prophet did not object. Water retaining its purity after being heated is considered like water that has been cooled.
Supporting text
The view of Mujahid, who seems to express disapproval, is noted but without logical foundation according to the prevailing opinion.