On Mon, 11 Nov 2002 22:24:33 -0800, "Steve Galupe"
wrote:

Even with a needle valve, the pressure will change. It might cause the tank
to be overdosed with CO2.

Well, with a regulator, the output pressure shouldn't change even if
the tank pressure increases. My room temp (and therefore the temp
of the CO2 tank in the room) varies from about 55F up to 90F, and the
output pressure of the regulator never varies, by even 1 psi. That is
really the job of the regulator. Regulators often have a problem
when the tank pressure drops to a VERY low level, normally somewhere
under 400psi, which only happens when the tank is just about empty.
On my regulator, the output pressure is set at a rock-solid 7 psi, but
when I am just about out of CO2, the output pressure has risen to
around 12psi. With a needle valve in the system, the impact is still
zero.

But, it's still not a good idea to keep the CO2 tank in a place that
will cause it to heat up, because if it heats up enough, it can build
up to a dangerous pressure, which would cause a safety valve in the
regulator to blow, releasing CO2 into the room.


Chuck Gadd
http://www.csd.net/~cgadd/aqua