The temple has the east-facing shrine of Naanmadiya Perumal holding a precious conch. In this temple, the incarnation of the Vishnu worshipped Lord Shiva in order to attain the famous conch also known as Panchajanyam. In the same village is located an equally famous temple known as Sayavaneswarar which is dedicated to Lord Shiva. It is believed that Lord Vishnu worshipped Lord Shiva at this place.

As far as the temple history is concerned, it is believed that during the time when the Gods and the demons were churning the milk ocean in the pursuit of nectar, the moon appeared before the Hindu Goddesses of wealth and as her elder brother. In yet another version, it is told thus that the moon God was born to sage Athiri and his wife Anusuya. From the Hindu scriptures, it is understood that the moon god is handsome and very well versed in different scriptures. He conducted a ritual that was attended by a number of sages as well as the wife of Jupiter. Owing to mysterious circumstances, Jupiter got enraged with the moon god and reported the same to the Lord Vishnu. Some say that the Guru, Sage was so enraged that he abused and cursed his disciple.Owing to a love affair of the Moon god, Mercury took birth. However, very soon the relationship between moon and his wife was estranged and their son was grieved at this sequence of events. He engaged in severe penance and took the form of a planet.

The opening time of Thalachangadu Naanmadiya Perumal Vishnu Temple Nagai Tamil Nadu is from six to 11 in the morning and from five to eight in the evening. The temple has a website of its own where details pertaining to its location and contact information are provided for interested viewers to browse. In Hinduism, it is believed that the moon god and other gods had worshipped this incarnation of Vishnu. From an astrological point of view, this temple has enough significance. Many believe that this temple is meant for those who are encountering adverse effect of the planet moon. The greatness of the temple lies in the fact that the shrine of Perumal has a crescent moon adorning atop his head quite similar to that of Lord Shiva. The deity is East facing and in a standing position. The deity is also known by other names like Chandra Shaba Harar and Nanmadhia Perumal. Sanctum sanctorum of temple is present in the Vimana tower also known as the Chandra Vimanam.