1. (a) Boilers. The Texas Boiler Law, Health and Safety Code, Chapter 755, and rules, regulate the safe construction, installation, inspection, operating limits, alteration, and repair of boilers and their appurtenances. All who perform any work regulated by and not exempt from this law and rules must comply with them, regardless of the type of license held.

2. (b) Electrical connections.

   1. (1) The new construction of environmental air conditioning, commercial refrigeration, and process cooling or heating systems begins after the first connection on the line side of any listed appliance.
   2. (2) Air conditioning and refrigeration contractors licensed under this law may replace and reconnect environmental air conditioning, commercial refrigeration, process cooling or heating systems, or component parts of the same or lesser amperage. On replacement environmental air conditioning, commercial refrigeration, process cooling or heating systems where the electrical disconnect has not been installed and is required by the National Electrical Code, the air conditioning and refrigeration contractor may install a disconnect directly adjacent to or on the replacement system and reconnect the system.
   3. (3) Control wiring of 50 volts or less may be installed and serviced by an air conditioning and refrigeration contractor licensed under this law.
   4. (4) All component parts may be serviced or replaced by an air conditioning and refrigeration contractor licensed under this law.
   5. (5) All electrical work shall be performed in accordance with standards at least as strict as that established by the current National Electrical Code.

3. (c) Piping.

   1. (1) Fuel gas piping for new or replaced environmental air conditioning, commercial refrigeration, or process cooling or heating systems may be installed by a contractor licensed under this law. Fuel gas piping by a licensed contractor is limited to the portion of piping between the appliance and the existing piping system, connected at either an existing shut-off valve or an existing opening for such use. Existing piping systems, stops, or shut-off valves shall not be altered by a licensed contractor.
   2. (2) Drain piping associated with environmental air conditioning, commercial refrigeration, or process cooling or heating systems may be installed by a contractor licensed under this law if the connection is on the inlet side of a properly installed trap.
   3. (3) Mechanical piping associated with environmental air conditioning, commercial refrigeration, or process cooling or heating systems shall be installed by a contractor licensed under this law.

4. (d) Duct cleaning.

   1. (1) Duct cleaning and air quality testing, including biomedical testing may be performed by an unlicensed person or company if:

      1. (A) the task is limited to the air distribution system, from the discharge of the unit to the inlet of the unit;
      2. (B) no revisions are made.
   2. (2) Revisions include cutting the duct, changes in electrical connections, disassembly of any part of the system other than access panels or doors, return air grills, or air duct registers.
   3. (3) Biomedical testing may be performed by an unlicensed person or company. Biomedical remediation requires a license.

5. (e) Process cooling and heating.

   1. (1) Process cooling and heating work does not include cryogenic work.
   2. (2) Process cooling and heating is limited to work performed on piping and equipment in the primary closed loop portions of processing systems containing a primary process medium. Once a primary closed loop process system has been deactivated and rendered inert, a non-licensed person may perform repairs on piping, heat exchangers, and vessels.

Source Note:The provisions of this §75.100 adopted to be effective January 28, 1993, 18 TexReg 301; amended to be effective January 7, 1994, 18 TexReg 9929; amended to be effective March 30, 1995, 20 TexReg 1887; amended to be effective October 1, 1995, 20 TexReg 7280; amended to be effective January 10, 1997, 22 TexReg 737.