Pressure Test Air vs Water

Nik

it seems like there is no industry standardized testing methodology for pressure testing radiant piping. From what I have read the decision of using air versus water is mainly related to safety. Are there other issues in terms of accuracy/reliability depending on what is used?



The following is commonly found in radiant glossaries regarding pressure testing:



The introduction of helium, nitrogen, oxygen, or other type of air to pressurize the system for testing is not an acceptable test and will likely result in inaccurate conclusions.



What are the issues other than safety?



Also, there seems to be a huge range of suggested pressures that these tests should be performed at. I have seem as low as normal operating pressure all the way up to 120PSI. I have read that code requires a hydrostatic test at 100PSI.



Is it possible that at low pressure and cold temperatures some leaks do not show up?



Thank you in advance for any information or opinions.

Gordy

Air vs Water

Air will give you a more stable reading, and it does not freeze..... that's your safety.

Gordy

PSI and temperatures

  Usually 100 psi, I guess you could go higher so long as the pressure rating of tubing, and fittings is not exceeded.



 If workmanship is border line then yes testing at lower pressures may not reveal a leak that may show up at a higher PSI. Temperature could play a role in this also thinking expansion contraction from low to high temps.





You can hydrostatic test, but the water in the system would have to aclimate to the surrounding temperature before any kind of baseline can be established.  Think expansion contraction of system components. If the enviroment has wild swings in temps during testing it will reflect in your readings.



Gordy



 

NYplumber

acceptable

Is 10psi over 48hrs an acceptable measurement of pressure loss?