I've had them recertify them. They are pretty quick. Best to bring it in empty if you want them to do that. They can also replace valves. But again, best if empty.
They do, but they ALWAYS have an extremely long line because they are doing a ton of fleet work, so I would not take it here as they have turned me away 4 times and also tried to sway me to $&#@ing home Depot and Lowes to get them done....
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