From a sales site, consumer information on buying heating and air conditioning and on hiring a contractor for installation.

Information and support on heating, ventilation and air conditioning systems or controls for home owners and professionals. Knowledge base, recalls, forum, glossary, and events.

The site identifies which products reviewers like and dislike, where they agree or disagree, and why.

EPA site with homeowner information for consideration when purchasing or repairing a residential system or heat pump.

Information on buying and maintaining air conditioning systems.

Step-by-step instructions on how to buy an air conditioner.

Describes air conditioning from window units up to large industrial applications.

Brand name product site. In addition to Carrier information, also has pages with consumer information such as what size air conditioners to buy for both home and industrial use.

Extensive information on all aspects and variations of cooling, air conditioning, including consumer information on how these appliances work and what to look for.

Consumer reviews, price information, related appliances, buying tips and advice, ratings.