Pipework Pressure Testing

[Mikebuk]

Hi All,
I'm new to air con and would appreciate some info from you guys.
My question is with regard to pipework pressure testing and the gas type used. I understand that oxygen free nitrogen is prefered, but could any inert gas be used? I ask as I have access to an unlimited supply of pure argon. Is pure argon an option? If not, why not? Thanks in advance.

[Brian_UK]

Now there's a question that comes around now and again.

Have a look here Mike......
http://www.refrigeration-engineer.com/forums/showthread.php?t=8951&highlight=argon

[Argus]

.

OFN is essential, not preferred. Any oxygen in ordinary industrial grade Nitrogen in contact with oil can be lethal. Plus it may contain moisture and other impurities.

Similarly, welding grade or commercial grade Argon may contain impurities that you may not want in your system.


Why not stick with the tried and tested methods?

.

[Peter_1]

Argon is also an inert gas, so why not?
Legally, he can use it anyhow.
If you look once to the Material Safety data Sheet, you will notice that Argon is 100% pure with no impurities.
http://praxair.com/praxair.nsf/AllContent/D03E8B4AA7B2958785256A86008095F7/$File/p4563h.pdf
and
http://encyclopedia.airliquide.com/sds/en/003A_AL_EN.pdf

[Brian_UK]

Also, of course, because the Argon molecules are larger than those of nitrogen it will not show up the smallest leaks.

[wambat]

If I were working on centrifugal compressors again I would defintely try leak detection using the hydrogen method. THis is becoming
more common in industry. One reason for this
is that hydrogen is the cheapest tracer gas available.
The actual gas mix used is a safe mixture of 5%
hydrogen in nitrogen. Another reason is the inherent characteristics of hydrogen. Hydrogen is the lightest and least viscous of all gases. It spreads very quickly throughout the test object and seeps quickly through the smallest leak.

Background interference is easily minimized because of the speed with which hydrogen dissipates.The method requires no pumps or vacuum and only needs a minimum of maintenance.