About Us

Initiated in a modest way by Late Pramod Kumar Khanna in the year 1966, the company started operating from a garage which served as an office, work-shop, service centre and later also as a godown for excisable goods.


In 1984, when manufacture of air conditioners by unorganized sector was practically unheard of, firm started assembling air conditioners under the brand name “DIAMOND Air Conditioners”. Very soon DIAMOND Air Conditioners became a prominent name in Eastern India. Workmanship, after sales service, punctuality, and reliability being the hallmarks of the Organization.

The firm was converted into a private limited company named as “Reliable Air Conditioners Pvt. Ltd.” in 1997 and brand name DIAMOND Air Conditioners was registered as Trade Mark with Registry. Today it has a spacious infrastructure of office premises, godown, workshops, and a service centre. The workforce includes more than 40 skilled technicians, supervisors, and engineers & a full team of Sales Personnel.

After catering to a group of elite organizations in both private and public sectors for over 45 years, the company is now a major name in Kolkata for Air Conditioning, Refrigeration, Electrical Engineering and allied businesses.

In 1998, Company diversified into display of Clients’ Advertisements on Electronic Moving Message Bill Boards. Presently it has ventured into Online Marketing - Search Engine Marketing, Mobile advertising and Social Media Marketing under the brand name DigiAds.