Vacuum testing

[leadslinger]

I have a large 2k ton york chiller and made a couple leak repairs yesterday. After pulling the system into a deep vacuum to test for leaks I got these numbers. 1.116 microns after vac complete. with oil heater still on and 1 hour later my vac was 1.516, an increse of 400 microns. Does this seem normal or do I still have a significant leak?

[install monkey]

keep monitering it- ur initial increase is normal, if it still increases then keep vaccing- could just be refrigerant migrating out the oil.
after all you did pressure test it and all was ok

[martinw58]

you might have moisture in the system

[monkey spanners]

Is that a 2000ton chiller? Just a guess but is it possible on something that size it may take a while for the vacuum level to even out, depends where your vac gauge is etc

[1mikeefc1]

Surely a pressure test would have brought a leak to your attention not the evacuation?

[Brian_UK]

I am confused with your numbering system, sorry it's a UK thing...

You say you have a micron reading of 1.116 which to me is 1 decimal 116 microns or are you saying that you have a reading of 1 thousand 1 hundred and 16 micron? If it is the one thousand plus reading then it is not a deep vacuum yet.

[al]

What type of chiller? YK/YS or air cooled, if one of the first two you may never attain deep vacuum given that there is a shaftseal present, if air cooled you need better numbers but keeping the oil warm will help.

alec