Fills dry or in water bath?

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The most reputable dive shop I've ever visited (and now frequent) does wet (water bath) fills. I can imagine water getting in the cylinder if it's done carelessly, but I don't see anything inherently wrong with cooling the tank while filling. The compressed air is bone dry so claims of "condensation" are nonsense.
 
The most reputable dive shop I've ever visited (and now frequent) does wet (water bath) fills. I can imagine water getting in the cylinder if it's done carelessly, but I don't see anything inherently wrong with cooling the tank while filling. The compressed air is bone dry so claims of "condensation" are nonsense.

Bingo! We have a winner
 
I'm more concerned with whatever vessel you're using to contain the water contributing to the high velocity airborne particles in the event of a catastrophic failure of the cylinder. There's a reason commercial filling boxes are steel, thick, and designed to contain a ruptured cylinder. A cattle trough full of water is a poor substitute. I understand dive shops typically don't have the time to fill slowly, but a tank monkey and a water bath just aren't great ideas. Doesn't take much for an idiot to do something wrong.

Check around the 1:40 mark.
 
There is a lot of discussion as always about filling wet. I have never had a problem with it. the argument against it is that filling dry allows no water in the tanks. I can tall you that if you have a 5cuft compressor and you are filling off of it that tank will get hot. If I cant fill wet, I wrap a wet towel on the tank. The belief is that( and it is true) that if you fill slow enough the tank will not get hot) no shop has that turnaround time for tank fills. put the whip on the tank than put the tank in the water and no problem. Quite often I put the tank in the water to cool it from being in the hot car. The head proponents persist in using a one rule fits all when it comes to wet/dry fills. Wet or dry you sill still get water in the tank unless you dry the valve after removing the regulator. Not to mention water getting into the reg. No one is concerned about that it seams. wet or dry use common sence and all is OK.
 
I took the PCI class and they suggested not to water fill. We've been filling tanks since the fifties I'm a third-generation diver and I can tell you without a doubt The fill is better in a water bath.. I made an attempt to defy my family history and the results were time consuming tedious filling operations. We use cool well water daily fresh. I am not a tank monkey I am a local fill station operator who believes the anything I can do to give my customers an efficient better fill is worth doing. We Bank 5000 PSI in our Cascade and the air goes through your standard Lawrence Factor filters changed out before scheduled intervals the, auto bleed system works flawlessly and our air continually test clean O2 compatible. I would be worried if another fill station operator did not know as much about their personal fill station system as we did however I cannot worry about what other people do only what I do.

The PCI class stated that the thermal conductivity was so low on scuba tanks that it didn't make a difference. I also fill aluminum tanks in the water bath and I can tell you from personal experience over probably close to 10,000 air fills the water is working in the way of what you anticipate cooling the fill. Again I could see how water could get in there where the bad operator however the whole idea is to avoid bad operators and just a quick glance at how they work should be enough to tell you whether you need to get your tanks filled somewhere else.

Worth adding is if I do hot fill a steel cylinder and pull it out of the bath it will still settle quite a bit. The trick is to still fill slow and let the tank settle in the bath while hooked up to the filling regulator. I can't imagine anyone would do any differently but I don't know how everyone works. We use Aqua environment regulators on our fill panel and I am able to dial the pressure and use the line valve to control the flow rate.

The occasional dry fill that I do is typically because the gentleman bringing the doubles and did not remove his back plate and harness setup I don't care particularly too well to put the gear in tub because it just makes a big wet mess taking it out of the store.

Everyone has their preference this is mine.
 
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I took the PCI class and they suggested not to water fill. We've been filling tanks since the fifties I'm a third-generation diver and I can tell you without a doubt The fill is better in a water bath.. I made an attempt to defy my family history and the results were time consuming tedious filling operations. We use cool well water daily fresh. I am not a tank monkey I am a local fill station operator who believes the anything I can do to give my customers an efficient better fill is worth doing. We Bank 5000 PSI in our Cascade and the air goes through your standard Lawrence Factor filters changed out before scheduled intervals the, auto bleed system works flawlessly and our air continually test clean O2 compatible. I would be worried if another fill station operator did not know as much about their personal fill station system as we did however I cannot worry about what other people do only what I do.

The PCI class stated that the thermal conductivity was so low on scuba tanks that it didn't make a difference. I also fill aluminum tanks in the water bath and I can tell you from personal experience over probably close to 10,000 air fills the water is working in the way of what you anticipate cooling the fill. Again I could see how water could get in there where the bad operator however the whole idea is to avoid bad operators and just a quick glance at how they work should be enough to tell you whether you need to get your tanks filled somewhere else.

Worth adding is if I do hot fill a steel cylinder and pull it out of the bath it will still settle quite a bit. The trick is to still fill slow and let the tank settle in the bath while hooked up to the filling regulator. I can't imagine anyone would do any differently but I don't know how everyone works. We use Aqua environment regulators on our fill panel and I am able to dial the pressure and use the line valve to control the flow rate.

The occasional dry fill that I do is typically because the gentleman bringing the doubles and did not remove his back plate and harness setup I don't care particularly too well to put the gear in tub because it just makes a big wet mess taking it out of the store.

Everyone has their preference this is mine.
Competence counts.

Also of note, the heat you feel in the water means it's working. I'm glad I don't have thousands of tanks to fill. If I did I would use water cooling and I would probably rig a cooling tower to maintain the water temp. Different sized tanks seems like it would be an annoyance to manage.
 
A few years ago - I would see only a few wet fill baths at my local shops. Every single one of these baths has disappeared. Owners and staff were all probably all thinking in agreement- why are we risking introducing moisture into these tanks during the fill process?

Nobody in Seattle is in a hurry...have you drove in Seattle traffic? Nobody here even wears a wristwatch. so, no sense of urgency. Ever. About anything. Go get your tanks in a few days.

All that time, too, and as maybe a separate post - I've seen way too many dive shops close and very few open. UW Sports in Everett, UW sports in Kirkland, NWSD in Kenmore, Bubbles Below in Woodinville, Scuba Set down in Federal Way,all closed up... some were dry fills since day one, and some wet fills that eventually went dry before closing up shop - but then any new shop that's opened recently is doing dry fills.
 
Someone tell me how water can defy the laws of mechanics and physics to slip through a valve that is closed.
I really need to know.
 
Push it in with the fill whip. It also atomizes the water and causes severe corrosion on the walls of steel tanks.
 
https://www.shearwater.com/products/perdix-ai/

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