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440hardtop
18-05-2009, 10:25 PM
When pressure/leak testing a system, what pressure should you charge the system to with nitrogen and what precautions should be taken in regards to pressure controls and other devices?

icecube51
18-05-2009, 10:36 PM
yo M8, always test on 1,1 times the maximum operating pressure given by the brand.

Ice

icecube51
18-05-2009, 10:39 PM
When pressure/leak testing a system, what precautions should be taken in regards to pressure controls and other devices?
look up the manual for by-passing the valves,or opening them on the main board.
it depends on the brand you are working on.

Ice

Frostycold
18-05-2009, 11:21 PM
Hi guys
I normally test VRF & Splits to 300psi/20bar, tap the guages & take a picture of the dials. When presure testing Chillers & other plant fitted with Safety Valves I check what the valves are set at & test to 20psi less than set presure. I've found that Safety valves, once blown, frequently will not reseat properly. I also find that it's worth looking for one way check valves on chillers with Screw Compressors as the check valves can prevent one from venting all the OFN resulting in NCG's in the system.
Regards
Frostycold

HallsEngineer
19-05-2009, 02:02 AM
You need to look at MWP of sytem normally 2 different values for high and low side. Then remove all PRVs and blank them off. Pressurise to 1.3 times MWP for strength test. The reduce the pressure for leak test to 1 or 1.1 times MWP. this is a good time to set your pressure trips ;). Then reduce back to zero and refit PRV's. This is a highly dangerous operation and the system should not be left during this operation. The other way is to look at your comparitor for the refrigerant and find the maximum design temp and pressure test to 1.3 times this pressure temp relationship.

nike123
19-05-2009, 03:26 PM
2886

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olelogolie
29-11-2010, 08:44 AM
I would like to get information and all specification of the VRV Systems

Thanks and regards.

Brian_UK
30-11-2010, 12:03 AM
Go to manufacturers websites.

El Padre
30-11-2010, 06:40 AM
Hi 440,

The guidelines here are High side = 55 Deg (Air cooled) 43 Deg (Water cooled) and Low side= 32 Deg, Strength test would be *1.3 pressure leak test * 1.1, it goes without saying to know the max pressures of each component in the system, as mentioned previously.

Just noticed the original post was in 2009, good luck with the Ashes! :cool:

Cheers

ashraf Bhatti
30-11-2010, 08:15 AM
what is standar valeu of supper heat & sub cooling in HVAC system desigened for pharma grade?

FreezerGeezer
30-11-2010, 11:46 AM
For the OP, be careful with chillers! Evaps often have a relatively low MWP. Chuck in 30Bar & you may well burst the gaskets, flooding the refrigeration circuit.
Trane's rule of thumb for leak testing was start with 10Bar. You'd be surprised - almost every leak showed up at that pressure. A very few times we went to 12Bar to find real pinholes. But their evaps are only PT'd to 14Bar, so we never went beyond 12Bar, just to be safe.

Indy2010
08-02-2011, 10:29 PM
Ok I'm confused here... If the high side normal working pressure for R400's and R500's is anything up to 15bar what pressure should we test to for strength and leak testing? Isn't this governed by code in the USA? I though it was twice the normal working pressure?? but heck I'm new..

FaultCode
08-02-2011, 11:37 PM
Check the Standards for your country, but all normal test figures are given in the posts above.