trying to fill SCBA tank with GX CX CS4

Its working, took it almost 10 minutes to move off the zero psi and about 20 minutes to get to 80 bar. Was just impatient.


Compressor is a GX CS4.....Bought SCBA tank off ebay and the Amazon 59.00 fill adapter, hook my hose up to fill nipple on adapter, close bleed valve and control valve on tank turn on compressor and begin to fill..its a 30 minute tank how long should it take before guage moves off of where it says 0 psi.. After 5 minutes it doesnt seem to move much at all but when I shut compressor off there also doesnt seem to be much pressure in hose but if I open control valve air comes out of tank thru hose.
This is 1st time trying to fill a SCBA tank so must be doing something wrong or Im not waiting long enough to see results.

Compressor fills guns just fine so know its working ok. Also doesnt seem to be any leaks.
Ideas suggestions appreciated or video link to maybe show me what Im doing wrong, the couple I watched I seem to be doing same thing. It has to be something simple Im not doing.
 
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A 30 minute tank will take a while before you see any movement with the CS4.. It's a slow moving low heat compressor but will do the job. If you're worried about whether or not it's got a leak etc.. Just put the dead head on the fill whip and set it to your desired pressure and turn it on. After it fills the hose look at the pressure gauge and see if it leaks down quickly. It will eventually leak down but I'm talking about 5 minutes. If it's holding in the whip, it's filling the tank. Be patient on the first scba fill. Fills after this will only to 250 bar etc, depending on your airgun desired refill pressure and will top off much faster.
 
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A 30 minute tank will take a while before you see any movement with the CS4.. It's a slow moving low heat compressor but will do the job. If you're worried about whether or not it's got a leak etc.. Just put the dead head on the fill whip and set it to your desired pressure and turn it on. After it fills the hose look at the pressure gauge and see if it leaks down quickly. It will eventually leak down but I'm talking about 5 minutes. If it's holding in the whip, it's filling the tank. Be patient on the first scba fill. Fills after this will only to 250 bar etc, depending on your airgun desired refill pressure and will top off much faster.
Thanks it seems to be working fine now, at 1 hr 5 minutes fill time and tank is at 150bar.. read it takes 2 hrs or so to fill 30 minute SCBA tank so right on schedule. Bleeding air every 6-8 minutes, temp is running around 34-35c 0r 93-94 deg f
 
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Well at 1hr 56 min tank was at 4100 psi and the cheap ass Chinese burst disk on the fill valve burst so now I have to start all over what BS.
Both gauges on compressor and fill valve were reading almost identical so know they were correct.
Ugh. That sucks. I have that problem with my air filters.
I fill to 300bar and have to stop there( my tanks are 310bar) Or the filter burst disk blows.
Best fittings makes a one way valve that I use inline so if the filter burst disk goes, it does not dump the tank. They're around $20 US.
I'm thinking of getting a second one to use as well, so the air won't go into the filter till it is at tank pressure, and then the second one at the tank in case the burst disk goes. It's also nice because you can turn on the compressor and just open the tank valve and don't have to wait till the compressor is up to tank pressure and then open it.
 
What sucks is it seems like all burst disc are made in China, this one was brand new so it had zero wear on it. Just ordered 3 more 6k disc but going to be really mad if I fill it again and it does same thing.
Times Sound right.
I also have a gx4.
Do you not have a filter on it?
Dumping the lines that often is going to make filling your tanks very slow & a real chore.
I have a small filter on it, need to get a bigger one. Was just trying to make sure no moisture got by.
 
What sucks is it seems like all burst disc are made in China, this one was brand new so it had zero wear on it. Just ordered 3 more 6k disc but going to be really mad if I fill it again and it does same thing.

I have a small filter on it, need to get a bigger one. Was just trying to make sure no moisture got by.
Yes, the 300bar (4351) burst disks are actually 6000psi rated, but they're for a 300bar fill system.
I also bought a bag of 6000psi ones as I run two molecular seive filters in parallel and They burst around 4300-4500psi. It's a pain because I'm running a CF 700CC air tank and with my 45min scuba tanks that takes a lot of air out of the tank, and only filling to 300bar tops, just makes it all the more of a drain overall. That's why I have a couple of them-
Best of luck with the new set up. Having a compressor has been a game changer for me and I love it!
 
In the words of a 70's TV Shoalin priest, "Patience Grasshopper". You're probably not doing anything wrong. These compressors only move a minute volume of high pressure air per cylinder stroke. I've seen it take 13 minutes of run time to get the needle to start moving on an empty tank. That's why I NEVER run a tank dry, only go down to 3200psi. Depending on tank capacity it can take 7-10 minutes per hundred lbs of pressure to move my gauges. Be very patient & you'll be fine. It's only costing time (& electricity).
 
I put a one way valve on after having issues with O-rings in my moisture filter. I put the one way at the exit of the second filter. Air can flow from the compressor to the tank but not from the tank to the filter or compressor. Simple, cheap, and highly recommended. Also allows me to open the tank valve right away instead of trying to time the point where the compressor and tank pressure is the same.

I don't remember the fill time the first time I filled my 45 minute tank from my YH but it took several runs. Now I fill from ~3200 to 300bar in one 15-20 minute run (that is quite noisy). I think the motor of the CS4 is about 20% the size of the YH so it should take about 5 times as long. I think the CS4 looks like a fine compressor with several advantages but fast fills of tanks isn't one of them.