Robert Bosch GmbH, Lennox International and Samsung Electronics are among the industrial firms competing to acquire heating and ventilation assets worth over $6 billion from Johnson Controls International, people familiar with the matter said on Friday.

Milwaukee-based Johnson Controls has been working with its advisers to sell its residential and light commercial businesses, including includes a US business and a 60 percent stake in an air-conditioning venture with Japan's Hitachi called Johnson Controls–Hitachi Air Conditioning, the sources said, requesting anonymity as the discussions are confidential.

The sources said other bidders could emerge, and any deal, if one emerges at all, is still months away.

Bosch, Lennox, Samsung and Johnson Controls did not immediately respond to requests for comment.

Johnson Controls has been attempting to divest the portfolio of heating and ventilation assets as part of its efforts to jettison non-core businesses.

Founded in 1885, Johnson Controls makes a wide range of appliances and equipment for commercial buildings, as well as home comfort appliances. It provides electronic systems for offices, schools and hospitals in areas such as ventilation, security and fire detection.

Johnson Controls' shares, which have risen about 12 percent so far this year, closed at $63.75 on Friday, giving the company a market capitalization of about $43 billion.