While still accessible, all pipelines must be pressure tested using water, air, or a mix of the two. The test pressure must be 1.5 times the operating pressure or 150 psi, whichever is higher. Testing below 150 psi may not reveal joints that have been improperly fused.
When performing the pressure test, the material properties of Aquatherm pipes can lead to an expansion of the pipe. This influences the test results. The coefficient of thermal expansion of Aquatherm pipes can also further influence of the test results. Different temperatures of the pipe and the test medium lead to alterations of pressure. A temperature change of 18 °F corresponds to a pressure difference of 7.25 to 14.5 psi (0.5 to 1 bar). Therefore the highest possible constant temperature of the test medium must be measured during the pressure test. If possible, allow for the temperature between the pipes and the test medium to reach equilibrium before reading the meter.
The pressure test requires a preliminary, principal, and final test.
For the preliminary test, pressurize the system to 150% of the maximum operating pressure (MOP). Expansion of the pipe and changes in temperature may cause the system to drop below 150% during this test. If necessary, the tester may add pressure until the system stabilizes at 150%. Once the system is stable, begin timing 30 minutes. The system must not lose more than 9 psi (0.6 bar) in that time. If any leakage appears, stop the test and repair the leaks before proceeding.
Immediately after successfully completing the preliminary test, begin the primary test. For the primary test, monitor the system for 2 hours, making sure that it does not lose more than 3 psi (0.2 bar) in that time.
Following a successful completion of the primary test, bring the pressure down to 0. Then repressurize the system to 150% of the MOP. After 2 minutes, bring the system down to 15% of the MOP. After 2 more minutes, bring the system back to 0 and repeat this process 3 more times, with a final interval of 5 minutes. This rapid cycling of the pressure will ensure that all the fused connections were properly installed.
NOTE: The times for the preliminary and primary tests are based on large installations, where small leaks may take longer to manifest as a pressure loss. For smaller installations such as single family homes, the times may be reduced up to 50% if no loss of pressure is detected in that time. The times on the final test do not change in any circumstances.
Measuring the Test Pressures
Measuring must be done with a pressure gauge allowing a perfect reading to 0.5 psi. In a multi-story installation, the pressure test should be conducted at the lowest point in the building that can be easily accessed.
A record of the pressure test must be prepared and signed by the client and contractor stating place, contractor installer number (found on the training certificate), and date. A system can be tested in phases provided that every heat-fused connection is eventually tested and that the tests are properly documented upon completion. The most recent version of the test record can be found here.
This test is designed to identify damaged pipe, manufacturer's defects, and poor workmanship. It is required by the manufacturer for the validation of the Aquatherm warranty*. This does not supersede or replace regulations placed by the local code authority having jurisdiction. To prevent back-dating, Aquatherm requires that this test be submitted before the system begins full operation.
Test should be faxed to Aquatherm at:
Tests may also be e-mailed to:
*Aquatherm’s warranty does not cover failures caused by improper installation, operation outside of the recommended parameters, or damage from mishandling after the pipe has left possession of the manufacturer.