Space conditioning systems that do not meet the definition of Entirely New or Replacement Space Conditioning Systems shall be considered Altered Space Conditioning Systems. Change-outs are further classified by whether they involve refrigerant containing components. Examples of change-outs that may trigger HERS verifications include: Installing or replacing a furnace, air-handler, heating or cooling coil, condensing coil or adding/replacing >40' of ducts in unconditioned space.