Short fills

[Wijbrandus]

How often do people get short fills on their tanks? Right now I rent my tanks, and they always seem to be running around 2800 instead of 3000.

What do you do about it? ***** afterwards? Or do you actually pressure test your tanks when you pick them up? That seems to be a lot of trouble, but is certainly starting to look like what I need to do.

Right now, 200 or 300 pounds isn't a big deal, but I'm still feeling gipped.

 

[Uncle Pug]

Before you leave the store ask them to top the tank up to rated pressure. Around here we have had the opposite problem at one particular shop.... 4 grand in a hp tank isn't uncommon.

 

[diver_paula]

I stopped getting fills at the store that always short fills. Before that, I watched them fill 'em &/or checked them before I left the store. & always check 'em before getting on a boat.

Paula

 

[partridge]

You can ask them to top it off when you pick it up. They usually lose that 200 psi from just cooling down. Shouldn't be too much trouble, maybe half a second on their huge air banks.

I hate short fills also because I usually scooter around at 5 to 10 feet just using up the air.

 

[paulwlee]

It has been my experience that I very rarely get the full 3000psi on a fill.
This is because the gas heats up when compressed, so when it cools down it is usually a couple hundred pounds short of full. The way around it is to get a top off after it has cooled down, or if you are renting, as in your case, check the pressure and then ask for a top-off if it's not full.

It is always a good idea to check the pressure anyway when you pick up the tanks, as mistakes do happen once in a while, and it's not good if you find out at the dive site that your 'full' tank is actually empty. AFAIK, most dive stores don't mind the divers checking the pressure before taking the tank.

 

[theskull]

Some good tips above, but is 200 psi really that big a deal? Really? How many additional minutes and/or breaths is it going to cut off your dive?

I consider 2400 to be a short fill. Anything above 2700 was a good fill before it cooled, anyway. I prefer 3200, fer sure, fer sure, but to complain it needs to be SHORT.

theskull

 

[Wijbrandus]

At my current SAC, I probably burn that just testing my regs.

I'm not really that worried about it right now. But someday, I'll be buying mix. Then it will matter to me a whole heck of a lot. Now, you can argue that that time is a long ways off. Decades, most likely. But it's out there.

Mostly I was just curious. If other people are getting fills below 2700 on a 3000 tank, I guess I have no room to complain, and I'll shut up now.

 

[r37691]

As others have said, There probably filling the tanks fast, when they cool you lose some psi. Thats why I fill my own.

 

[flounderboy]

You should always check them
I was out 60 miles and found a deco bottle at 2300 :11:
I checked the mix ,, not the amount
last time that will happen to me

Dive safe

Mark s

 

[Gary D.]

Sunday morning I stopped by the main fire station where we normally fill at. We never worry about short fills because these guys are good at getting the air in.

I packed my rig in, pulled the reg off and we started filling while the chief was training a new guy in the process. When we were done and I replaced my reg, turned on my air and went Yahoo 3800 pounds. The new guy’s eyes got to the size of grapefruit and the Chief started laughing.

He told the new guy if I had gotten a 3800# fill I would have never said a word but tiptoed out of the station with a big grin on my face.

The only short fills we get are off the Cascade System when we are filling lots of tanks.

Anyway, back on the shop subject. Check your tanks prior to leaving but if they top them off expect them to still drop a few pounds before you use them. A hot sunny day nay increase the PSI where a cold day may drop it some so don’t expect a 100% fill 100% of the time.

Gary D.