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kerrcell
30-11-2009, 07:43 PM
Hi All,
I came across a two door refrigerator,almost new that runs on pentane.Well call was as it was not cooling enough.I read a freezer temperature of -11 degrees celcius and 14 degrees celcius in refrigerator,well far from the normal temperatures expected from my side.I was in the verge to install a pierce vale to check suction pressure but was faced with the problem to braze back the pipe.I have a crimping tool but obviously has to braze the pierced copper.What can be done with these newly designed refrigerators as pentane is highly flamable and do not think is a good idea getting close with a brazing torch ! Any help would be appreciated.

NoNickName
30-11-2009, 08:28 PM
Need to recall it and recharge.

kerrcell
01-12-2009, 03:57 PM
Yes but how about to close pierce of valve or shall I leave one installed there ?

NoNickName
01-12-2009, 05:31 PM
It won't harm to leave it there as soon as it's leak tight.

kerrcell
02-12-2009, 03:37 PM
Ok then will do it this way.But if there's a circumstance that one has to open system,how can he braze if the gas is flamable ?

desA
02-12-2009, 04:29 PM
^ I'm not sure what the other members may suggest, but I'd recover refrigerant, vacuum, purge with OFN (repeat at least 2x), measure pentane levels % - check not near explosion point - set strong OFN purge, get brazing.

This kind of thing is done in refineries & chemical plants routinely. There will always be some level of risk, with refrigerant hiding in system. A good OFN blanket is useful.

Not sure if there are other better blanketing gases around. I'd be interested to hear comments.

With this kind of job, I'd take along a spare pair of underpants - you may need them. :)

NoNickName
02-12-2009, 08:28 PM
Ok then will do it this way.But if there's a circumstance that one has to open system,how can he braze if the gas is flamable ?

you can't, as DesA explained.

spimps
03-12-2009, 07:54 AM
Supco answered an email in which I asked if their peircing valve is considered suitable for use on hydrocarbons and they answered yes.
They are a permanent fix when fastened down after testing.

kerrcell
03-12-2009, 03:51 PM
Ok thanks so better keep a fire blanket just in case.