PEX-AL-PEX composite pipe shall comply with ASTM F 1281.
PE-AL-PE composite pipe shall comply with ASTM F 1282.
Composite piping shall be marked at intervals by 5 ft. (1.5 m) with at least the following:
(a) ASTM F 1281 (PEX-AL-PEX) or ASTM F 1282 (PE-AL-PE);
(b) Material type – PEX-AL-PEX or PE-AL-PE;
(c) Code of material and manufacturing date.
(d) Manufacturer’s trademark or name;
(e) Piping;
(f) Mark of an acceptable certification agency;
(g) Pressure ratings for water and the temperature for which the temperature rating is valid;
The elevated temperature and pressure ratings for PEX-AL-PEX and PE-AL-PE in accordance with ASTM F 1281 and ASTM F 1282 are:
Thermal Expansion
Expansion rate for PEX-AL-PEX and PE-AL-PE is 1.56 in. (39.6 mm) per 100 ft. (30 m) of tube per 100°F (55°C) change in temperature. No accommodation for thermal expansion is required.
Pressure Relief Valves
PEX-AL-PEX piping used for temperature or pressure relief valve drain lines shall be graded to the outlet end and shall be supported by a maximum of 8 ft. 2 in. (2,489 mm) interval horizontally. Vertical piping shall have a mid-story guide and shall be supported at every floor.
Heated Joints
When soldered and welded joints should not use an open flame.
Working Pressure and Temperature
Long term working pressures for the PEX-AL-PEX shall not exceed a maximum of 125 psi (860 kPa) and the long term working temperature shall not exceed 180°F (82°C). Long term working pressures for the PE-AL-PE shall not exceed a maximum of 100 psi (690 kPa) and the long term working temperature shall not exceed 180°F (82°C).
Water Heater Connections
PEX-AL-PEX or PE-AL-PE piping shall not be installed within the first eighteen inches (18) (457 mm) of piping connected to a water heater.
