Homeowners would be able to use a Web site, www.myappliance.com, to control the operating temperatures of their Carrier brand air conditioners from work or elsewhere. They could set back on the cooling when they leave for work in the morning, then change it again before they leave work for home. Dealers, installers, and engineers could diagnose mechanical trouble without home visits.

A pilot program will be launched this summer in Britain, Greece and Italy.