To add to the helpful advice from PigeonMan and 2D1C-
i just used my Lightning for the first time to fill a tank from zero to 4500. It was a SCBA 45 minute tank(THANKS AGAIN, GERRY!!), and I told myself even though the Hatsan instructions said to not ever exceed 195 degrees F in use, I made 185 degrees my cut off. So, that tank took me an initial 45 minute session, rest till it went down to 120 degrees, back on for another 30 minutes, stop. I am now at around 2500 psi. It was very late when I started the fill process, so off to bed.
Next morning, it was much warmer than the evening before, so after 30 minutes I hit 185 degrees, stop. I’m now at around 3400 psi. After a cool down to 120 degrees it took 15 minutes to get to the 4500 psi fill. So two hours total run time to fill that tank.
If I had planned it better, I like CENTERCUT’s suggestion he put out there awhile back, and that was to take your empty tank to a fill place, pay the $10 to fill, and just use our residential type compressors for top offs. It’ll help it last a lot longer for sure.
I, too have a 88 cu foot tank, and I always top off when I’m at or near 3200 psi. From past experience I’ve noted that it takes approx. 12 to 18 minutes to top off my tank back to 4500 psi. I set my auto purge to 10 minutes, to guarantee me at least one full blast of moisture removal. There’s a good amount of moisture that comes out with a purge. Be aware that setting your auto purge to come on every 10 minutes will also increase your fill time on a new tank, and that is why mine took so long to fill up. In hindsight, for a new tank fill that’s empty, I should’ve reprogrammed the auto purge to like every 20 minutes. The compressor drops pressure a bit after a purge, and has to build back up to continue with the fill.
Lastly, when bleeding the air at that aluminum block where your fill whip is attached to- when bleeding, have the air run past your fingers, and feel for moisture. There shouldn’t be any, but there will come a time that it will have some, and that means your inner desiccant inside that block needs to be changed out like ASAP.