I have a kegerator with a dual body co2 regulator. One unit with two regulators and set points. I've disconnected all kegs from the system. I set one regulator to 30 psi, I set the other to 10 psi. The 30 psi line is just a single piece of tubing with an inline disconnect (mcmaster 5923k43/5923k73) connected to a corny gas qd. The 10 psi line goes to a 4 way manifold and 4 co2 lines with standard corney gas quick disconnects.
After all of the tubing equalizes I turn off the co2 at the tank. Everything holds as expected for several hours. By morning the gauges read a higher pressure than the initial set point. The valve that displays the tank pressure shows a lower pressure by this point. Within a day or two the high pressure gauge shows 0 the other two gauges show lower than expected (10 and 30 psi) pressures. These pressures will drop for a day or two and then level off. When they do level off the pressures will not change.
There is some pressure on the high pressure side of the regulator even after the tank is turned off. I can see differences in temperature drawing this out over time. The tubing gets colder than the point I set it at, gas contracts and additional co2 is allowed to escape into the low pressure side of the regulators. That part makes some sense to me.
What does not make sense is the later drop and subsequent leveling off. Is there a leak that is not apparent at lower pressures? Do temperature fluctuations allow co2 to feedback into the high pressure side of the regulator? Or is this just a completely flawed method for attempting to detect co2 leaks?
