I have a reverse osmosis water filter with lots of ¼" poly tubing
and compression fittings. In a couple spots there is a leak between
the tubing and the fitting (not at the threaded end of the fitting). I
have tried replacing the tubing and connectors at those points, but
they still leak.

What is the secret to making good connections? There is no separate
ferrule - it seems to be part of the threaded connector. There are
no inserts that go in the tubing ends to stiffen the tubing at the
joint. I know not to over-tighten the connectors, and I try various
levels of tightening, to no avail. I don't think it matters how far
the tubing sticks out of the connector before the connection is made,
does it? Is there some other variable I need to alter? Why do these
connections seem so darn touchy? Even the RO filter change
instructions say to keep going back to check for leaks, like they think
the odds of failure are high.


Thanks,
Teffy

There should be a small piece of tubing ( insert) that fits inside the
poly. if it's a standard type compression fitting. The tube keeps it from
distorting.




"Teffy" wrote in message
oups.com...
I have a reverse osmosis water filter with lots of ¼" poly tubing
and compression fittings. In a couple spots there is a leak between
the tubing and the fitting (not at the threaded end of the fitting). I
have tried replacing the tubing and connectors at those points, but
they still leak.

What is the secret to making good connections? There is no separate
ferrule - it seems to be part of the threaded connector. There are
no inserts that go in the tubing ends to stiffen the tubing at the
joint. I know not to over-tighten the connectors, and I try various
levels of tightening, to no avail. I don't think it matters how far
the tubing sticks out of the connector before the connection is made,
does it? Is there some other variable I need to alter? Why do these
connections seem so darn touchy? Even the RO filter change
instructions say to keep going back to check for leaks, like they think
the odds of failure are high.


Thanks,
Teffy

"Teffy" wrote in message
What is the secret to making good connections? There is no separate
ferrule - it seems to be part of the threaded connector. There are
no inserts that go in the tubing ends to stiffen the tubing at the
joint.


Get the proper fittings. There should be an insert. You may also want to
consider using copper tubing and the proper fittings for that. Less chance
of a problem long term.