Heating and air conditioning refers to a heating and/or cooling apparatus consisting of an air heating and/or cooling fixture from pipes, plenums or blowers including any accessory and equipment installed in connection with it. The term excludes window units, and usually refers to building equipment, rather than automotive or farm implement type heating and/or air conditioning equipment.
Any individual or any regularly employed person for any partnership or corporation who for hire is engaged in the installation or service and repair of heating and air conditioning systems may be required to be certified under state laws, which vary by state. A certified contractor is authorized to install or service and repair or replace natural gas heating and air conditioning appliances, including specifically the servicing, repair, or replacement of those appliances in manufactured housing set up as stationary housing, but excluding the piping to such appliances, and except as otherwise prohibited by law. The public may request a list of certified contractors as provided by local law.
