Winter Tank Storage

[Oriskany]

I store my steel tanks empty, and make sure the valve is closed. The argument that you need to keep some pressure in the tank (300-500psi) to keep the moisture out doesn't make sense to me. If the valve can keep 3000 psi in, how can a closed valve let let moisture in. I wrote a letter to Bill High, president of PSI. He agree's and says that leaving some pressure in a tank was done by the gas industry to help people know the valve is actually closed. If your enough of a tech diver to know which way is open or closed, there is no need to store a steel tank with air in it. Having more air equals more oxy and can promote rusting if you have moisture in the tank. We all should know how a diver can let water in his tank, but sometimes its the professional filling your tank or a faulty compressor. I got moisture in my tanks because my compressor had a bad back pressure valve. The biggest problem I have seen is when the tank gets a hydro and the facility doesn't do a good enough job drying it out. My system is to VIP a tank in the fall and leave it empty, valve closed and if its put away looking good, it will look just as good in the spring.