mech9238
Mechanical
- May 10, 2019
- 6
Good Morning,
Trapped air in a sprinkler or hvac (condesner, chilled water) system and hydrostatic testing.
Hydrostatic test: min 200psi to max 450psi, Water with trapped air (cannot determine amount of air)
Reading online, testing with air at 30psi is equivalent to a 150 water test. (the viscosity is different between water and air)
At these pressures, pressure drops, no visual leaks, however pressure drops steadily over 1-2hrs. I have seen air leak out first than water after time.
Is it possible for trapped air in a 200psi or greater hydrostatic test to leak out and stabilize? (air can bleed out but not water?)
Material is (threaded connections, victaulic connections, etc.) I assume manufacturer's would say that air and water would leak out if the pressure is dropping?
The code does not differenate (pressure drops are fails) but sometimes questions arise in the field. Was wondering if anyone had an opinion or perhaps a physics answer to this?
Trapped air in a sprinkler or hvac (condesner, chilled water) system and hydrostatic testing.
Hydrostatic test: min 200psi to max 450psi, Water with trapped air (cannot determine amount of air)
Reading online, testing with air at 30psi is equivalent to a 150 water test. (the viscosity is different between water and air)
At these pressures, pressure drops, no visual leaks, however pressure drops steadily over 1-2hrs. I have seen air leak out first than water after time.
Is it possible for trapped air in a 200psi or greater hydrostatic test to leak out and stabilize? (air can bleed out but not water?)
Material is (threaded connections, victaulic connections, etc.) I assume manufacturer's would say that air and water would leak out if the pressure is dropping?
The code does not differenate (pressure drops are fails) but sometimes questions arise in the field. Was wondering if anyone had an opinion or perhaps a physics answer to this?