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Types of Mechanical Work That Do Not Require a Permit
Mechanical Permits are not required for the following: Portable heating appliances; Portable ventilation appliances and equipment; Portable cooling units; Steam, hot water or chilled water piping within any heating or cooling equipment or appliances regulated by this code; the replacement of any minor part that does not alter the approval of equipment or an appliance or make such equipment or appliance unsafe; portable evaporative coolers; and self-contained refrigeration systems that contain 10 pounds (4.5 kg) or less of refrigerant, or that are actuated by motors of one (1) horsepower (0.75 kW) or less. Replacement of natural gas-fired furnaces and boilers in attached and detached one and two family dwellings when there is a WSSC permit; Finishing single-family detached and attached basements when the work is limited to ductwork and exhaust fans; Replacement of components within a unit such as compressors and burners. Exemption from the permit requirements of this code shall not be deemed to grant authorization for work to be done in violation of the provisions of this code or other laws or ordinances of this jurisdiction.
Find more information from the following link(s):
  • Mechanical Permit