Approval

$$ 1355E\ 2div23 $$

$$ 20472023 $$

Revision History

1

Purpose

1.1 To establish a standard procedure for pneumatic leak testing of hydronic
piping (e.g. heating and cooling piping) assembled with press-type fitting
joints.

2.1 This procedure applies to all Therma projects requiring a pneumatic leak
test for the hydronic piping assembled with press-type fitting joints.

3.1 Therma’s general foreman is responsible for performing the tasks listed
herein.

4.1 California Mechanical Code, Section 1201.2.8, Chapter 12, Current Ed.

5.1 Foreman shall maintain safe working conditions throughout the process
of leak testing including provisions for pre-task planning, hazard
marking/signage and awareness, LOTO, pre-test inspections and
barricades, etc.

5.2 CAUTION : Pneumatic testing involves the hazard of released energy
stored in compressed gas. Particular care must therefore be taken to
minimize the chance of brittle failure during pneumatic leak test.

5.2.1 If a pneumatic leak test would present unacceptable hazards,
such as risk of brittle fracture at the metal test temperature, then a
substitute for pressure testing should be developed.

5.2.2 See ASME PCC-2 for information regarding the need for risk
analysis.

6

Procedures

6.1 Review the customer’s leak test requirements and the type of test
medium to be used for each type of the piping system.

6.2 Do not perform a pneumatic leak test unless the owner specifies or
permits its use. It is recommended to implement hydrostatic leak testing
method unless one or more of the following conditions applies:

6.2.1 The equipment, piping and/or supports, including foundations
cannot adequately support the liquid weight.

6.2.2 When the equipment or piping cannot be dried, and traces of the
testing liquid/medium may result in contamination of the system or
it’s contents after returning to service.

6.2.3 The equipment or piping contains internal lining that could be
damaged by the test medium.

6.2.4 When piping size is 6” or larger and where city water pressure is
too low to meet the required test pressure. It is necessary to
increase the test pressure.

6.3 Pressure Relief Device. A pressure relief device shall be provided having
a set pressure not higher than 110% of the test pressure, except that for
test pressures below 100 psi (700 kPa), the set pressure may be as high
as 10 psi (70 kPa) above the test pressure, but not higher than 1.5 times
the rating of the weakest component in the system.

6.4 Test Fluid. The gas uses as test fluid, if not air, shall be nonflammable
and nontoxic.

6.4.1 Use Nitrogen N 2 or Carbon Dioxide CO 2 gas as test medium. For
High Purity or Hygienic piping, use only certified high purity gas
for testing, record cylinder # and attach certificate of purity to the
test report.

$$ \mathrm {N} _ {2} $$

$$ {\mathrm O}_{2} $$

6.5 If required, connect to the test volume/boundary a calibrated test gauge
with temperature compensation, one-pound increments and Calibration
Certificate from the Quality Control Department.

6.5.1 Test Gauge Calibrated range should be approximately double the
test pressure and shall have minimum range 1.5x test pressure
and maximum range 4x the test pressure.

6.5.2 The test gauge shall be a high accuracy test gauge verified to be
tracking properly.

6.5.3 Record test gauge ID#, calibration date, range and Manufacturer/Model on the Leak Test Report Form # FN 6.004.1.

6.5.4 Ensure that the calibration is NIST traceable.

6.6 Complete Leak Test Report Form # FN 6.004.1 as much as possible prior
to Pre-Test and Test.

6.6.1 If required by project specifications, mark up a dedicated set of
drawings (e.g. P&ID) showing the limits of the test, by using a
colored marker. Indicate all removed devices on the P&ID with
next to the device.

6.7 Gross Leak/Pre-Test Preparation and Visual Inspection.

6.7.1 Examine the piping systems to be tested for visual defects and
ensure that all connections are tight.

6.7.1.1 Examine all joints for un-pressed and partially-pressed
joints.

6.7.2 Remove any instrumentation or equipment, which may be
damaged by higher test pressures. This includes gauges,
sensors, tank rupture disks, regulators, etc.

6.7.3 Attach “PRESSURE TEST IN PROGRESS” tags on all branch or
bleed valves.

6.7.4 Attach test assembly as shown in Diagram 1.

6.8 Pre-Test or Gross Leak Test - Pneumatic

6.8.1 Metallic Materials maximum pre-test pressure: 15 psig or one-half
(½ ) the design pressure, whichever is less.

6.8.2 Slowly pressurize the system with test gas to raise pressure to
pre-test pressure. Secure the supply and allow the system to
stabilize for ten (10) minutes before inspecting for leaks. Slowly
pressurize the system with test gas to raise pressure to 15 psig.

6.8.3 Allow system pressure to stabilize for a minimum of 2 hours.

6.8.4 If system pressure has dropped, add more air to bring the entire
system up to 20 psig.

6.8.5 If system pressure increases above 15psi, bleed off excess
pressure to ensure system is at a maximum of 15psi.

6.8.6 If the system pressure continues to drop, examine all joints for unpressed
fittings or air leaks using commercially available leak test
solution or a soap and water mixture where allowed.

6.8.7 Identify leaks found, safely vent system and make repairs to
leaking joints. Repeat until leak free.

6.8.8 Once the system has been confirmed to be leak free, complete
the Pre-Test portion of the Leak Test Report Form # FN 6.004.

6.8.9 Be sure to notify the owner or owner representatives to witness
and sign the Leak Test Report if required.

6.8.10 If no leaks are found and there is no pressure drop, proceed to
the Pressure Hold Test.

6.9 Pressure Hold Test

6.9.1 Test Pressure: The test pressure shall not be less than 1.1 times
the design pressure and shall not exceed the lesser of

6.9.1.1 1.33 times the Design Pressure

6.9.1.2 The pressure that would exceed 90% of the pressure
described in 6.9.1.3.

6.9.1.3 Reduced Test Pressure: If the test pressure would
produce a circumferential or longitudinal stress (based on
the minimum pipe wall thickness) in excess of yield strength at test temperature or is greater than 1.5 times
the component rating at test temperature, the test
pressure may be reduced to the maximum pressure that
will not exceed the lesser of the yield strength or 1.5 times
a component rating at test temperature.

6.9.1.4 For metallic bellows expansion joints, contact project
engineer for testing requirements.

6.9.2 Gradually increase the pressure in approximately 25 psig
increments until the test pressure is reached. Allow the system to
stabilize for ten (10) minutes before examining for leaks.

6.9.2.1 Do Not Exceed 5 psig on Non-Metallic systems.

6.9.2.2 Maximum Pressure: The test pressure shall not exceed
the maximum test pressure for any vessel, pump, valve or
other component in the test.

6.9.3 Wait until the test pressure and temperature is stabilized (i.e. no
continuous drop), complete the ‘Start’ Pressure Hold Test portion
of the Leak Test Report Form # FN 6.004.1.

6.9.3.1 Be sure to notify the owner or owner representatives to
witness and sign the Leak Test Report if required.

6.9.4 Maintain the test pressure for at least two hours (120) minutes.

6.9.5 Observe the test pressure reading displayed on the pressure
gauge. If the test pressure continuously drops, reduce to the Pre-
Test Pressure and perform visual inspection and repair any leaks.
Repeat Pre-Test per 6.8.

Note: The test pressure may fluctuate due to many reasons,
temperature expansion/contraction, chemical reaction, etc.

6.9.6 When the holding time is achieved, complete the ‘End’ Pressure
Hold Test portion of the Leak Test Report Form # FN 6.004.1.

6.9.7 Be sure to notify the owner or owner representatives to witness
and sign the Leak Test Report Form if required.

6.9.8 Once the system has been confirmed to be leak free, safely vent
pressure.

6.10 Replace/restore all removed instrumentation and reconnect all
equipment.

6.11 Remove all “PRESSURE TEST IN PROGRESS” tags.

6.12 Apply signature, print name and date the ‘System Restoration Completed
By:’ section of the Leak Test Report Form # FN 6.004.1.

Standard Operating Procedure SOP #: 6.010 Rev.0

Leak Testing-Piping with Press-Joints Page #: 7 of 8

7 Review and Approval

7.1 Therma’s General Foremen shall submit the Leak Test Report Form #FN
6.004.1 to Project Manager for review.

7.2 Therma’s Project Manager shall review the Leak Test Report Form #FN
6.004.1 and submit to owner for record.

THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION OF THERMA. ALL INFORMATION SHALL (A) BE RETAINED IN CONFIDENCE; (B) NOT BE REPRODUCED IN WHOLE OR IN PART; (C) NOT BE USED OR INCORPORATED IN ANY PRODUCT EXCEPT UNDER EXPRESSED WRITTEN AGREEMENT WITH THERMA.

Standard Operating Procedure SOP #: 6.010 Rev.0

Leak Testing-Piping with Press-Joints Page #: 8 of 8

DIAGRAM 1 – General Pneumatic Leak Test Assembly