Chapter: Troubleshooting
Topic:
LeakChecking your GC
There are 3 ways to chec k
for gas leaks in a GC.
The 1stmethod of leakchecking is
called "looking for bubbles" or
·snooping the fittings".
Snoo~
is
a specific brand of leak check
so–
lution, but SRI suggesls amixture
of isopropyl alcohol ( IPA )andwa–
ter. The alcohol reduces thesur–
face tension of the water so
it
flows into the cracks between the
tubing and the fitting. otherwise
water alonewould
be
fine.Don't
use soapy water because
if
the
leak c:tIec:k solution gets inside the
GCtubing or fittings,
it
will con–
taminate the system.
Apply gas pressure to the system
thenplace a droplet or
two
of leak
check solution on
the
tube con–
nections. If tiny little bubblesare
visibie then the fitting is leaking.
Using the liquid leak cheeksolu–
tioncan
be
difficult howeverwhen
there are many fittings
to
lest or
when some of the fittings arehot,
( thiswill rapidlyboll off the leak
check solution ) making it impossi·
bleto tell if therearebubbles from
a leak or bubbles fromthewater
boilingaway.
l iquid leak checking is the least
effective way to check for gas
leaks in a GC system.
A
low
<XlSl
diapo$8bIe
mOldical synnge
1$
perfeo:t
101
plac–
ing•
drop
~
_ _
ocOubon lIllhe
join!
wIlete
1M •
lube
and
It>e
fitling
meet.
A3m1....k_
syringe
is
prooo;ded
with
ever)'
SRIGC
Put
!he
leak
check
solution •
!he
joint
between
the
tube and ,
"''''
Sane
GC
syslftm$
may
~
many
pIat:es
where
leakscall occur,
