He was only five years old, when his father expired. His mother brought him to her parental family. He got education in that village. His mother too expired when he was 11 years old. His maternal father's family raised him. His maternal grand father, Sri Khan Chand Ji, was the person, who founded the city of 'Ukarha'. All of this family was a devotee of Sant Baba Nand Singh Ji. Therefore, from his childhood, Sant Harnam Singh Ji got auspicious opportunity to enjoy the company of Sant Baba Nand Singh Ji.

After studying up to 10th grade, he went to Sant Baba Nand Singh Ji and devoted himself to him forever. Getting the sermon from Sant Baba Nand Singh Ji, he put himself into the meditation and service. He used to do 'Katha' (exegesis) of Sri Guru Granth Sahib Ji visiting every part of country. He baptized millions of people and brought him on the path of meditation and service. He performed hard penance for 14 years in 'Kanniyan', where the dead body of Sant Baba Nand Singh Ji was put into the river Satluj.

From May of 20, 1984, he settled down permanently in city of Zira. On 14 January 1986, he founded the 'Gurdwara Dera Harnamsar' along with the five beloved ones and other saints.

'Saajan Sant Karoh Eh Kaam. Aan Tiyaag Japoh Har Naam.' (O friends, O Saints, make this your work. Renounce everything else, and chant the Name of the Lord).

While following the Gurbani, he left for his heavenly abode on November 13, 1989, the day of Sri Guru Nanak Sahib's birth anniversary.

'Gur Kirpa Jeh Nar Kau Keenee, Tah Eh Jugat Pachhaanee.
Naanak Leen Bhyo Gobind Sio, Jio Paanee Sang Paanee.

(That man, blessed by Guru's Grace, understands this way. O Nanak, he merges with the Lord of the Universe, like water with water).

Blessed by him, Sant Hari Singh Ji has at the present been looking after this place.

From 1962, he got the auspicious opportunity to serve Sri Maan Sant Baba Harnam Singh Ji and enjoyed his company. During his missionary-journeys, Sant Baba Harnam Singh Ji stayed in his house and preached in the region for several months.

Sant Hari Singh Ji studied up to ninth grade and since 1967, he dedicated himself fully to the service of Sant Harnam Singh Ji. He performed hardships for constant 22 years serving him. On November 13, 1989, when Sant Harnam Singh Ji left for his heavenly abode, five holy 'Sri Akhand Paathhs' (constant reading of holy scriptures) of Sri Guru Granth Sahib Ji were performed. On the day of 'Shardhanjali Samagam' (Tribute ceremony), all of the 'Sant Samaj' (the society of saints) appointed Sant Hari Singh Ji the next chief of the 'Dera' (abbey).

The body of Sant Harnam Singh Ji was cremated in the Gurdwara premises. His ashes were put into the river 'Satluj' at Sri Keeratpur Sahib Ji (Patalpuri) and Sri Bibhor Sahib Ji (Nangal) in the presence of great men and thousands of devotees.

Sant Hari Singh Ji does 'Katha' (exegesis) of Sri Guru Granth Sahib Ji. He arranges 'Amrit Sanchar' (Sikh baptism ceremony) and tries to bring people on the path of God. From November 13, 1990, the 'Kar Seva' (manual service by the community) was started in Gurdwara Dera Harnamsar. With the help of the community, main hall, community kitchen hall, pond, shoe-hall, and residential rooms have been constructed so far. The recitation of Holy Scriptures, 'Katha', and devotional music is performed daily. Every year on the day of 'Vaisakhi' (a festival) and on demand by the community, the 'Amrit Sanchars' are performed here in the 'Dera'.