(a) When there is a question or doubt about the extent of a defect found in a boiler, the inspector may require a liquid pressure test.
(b) In preparing a boiler for a liquid pressure test, the boiler shall be filled with water to the stop valve and all air vented off. If the boiler to be tested is connected with other boilers that are under pressure, such connections shall be blanked off unless they have double stop valves on all connection pipes with a drain between.
(c) During a liquid pressure test of a boiler, the safety valve or valves shall be removed or each valve disc shall be held to its seat by means of a testing clamp and not by screwing down the compression screw under the spring.
(d) The metal temperature for the pressure test shall not be less than 60 degrees Fahrenheit (16 degrees Celsius), unless the owner provides information on the toughness characteristics of the material for a lower test temperature, but the maximum metal temperature shall not exceed 120 degrees Fahrenheit (50 degrees Celsius), unless a higher temperature is specified and is acceptable to the inspector.
(e) When a liquid pressure test is to be applied after inspection, the pressure shall be as follows.
  (1) For all cases involving the question of tightness, the pressure shall be no more than the set pressure of the safety valve or valves having the lowest setting.
  (2) For all cases involving the question of safety, the pressure applied shall not exceed the lesser of that which was required by the original code of construction, or the pressure equal to that which results in an applied stress no greater than 90% of the specified minimum yield stress at test temperature of the material as published by ASME Code, Section II, Part D, current edition.
(f) A liquid pressure test shall be held for a minimum of fifteen (15) minutes at the required pressure without leakage
(g) The actual pressure in the boiler shall not exceed 1.5 x MAWP.

Source Note: The provisions of this §65.613 adopted to be effective June 15, 2015, 40 TexReg 3121; amended to be effective February 15, 2016, 41 TexReg 795