I've been filling my 45 minute Scott scba tank via my Yong Heng and it's seems like it takes way too long. From empty to 4000 psi is taking about 35-45 minutes. Does that sound normal?
From empty to 4000 psi that sounds right. I run mine in ten minute intervals. I'm on my 4th piston rebuild. You gotta be handy to have a cheap compressor
Normal, from empty. 3- 5 minutes per 100lbs of pressure is not unusual. Just be patient & after this don't let your tank go below 3,000psi before refilling from now on. That first FULL fill of the tank is a PIA, after that, smooth sailing. DON'T fill to full 4500psi. 4300 MAX! Makes compressor strain too hard for that last 200 lbs.
I agree. I fill from 3000 to 4000 or sometimes 300 bar in 15-20 minutes. That's about as long as I want to run it even when the temperature is OK. I'd rather have the tank at 4000 than do a second run to get to even 300 bar. I often don't fill my guns to the maximum either. Seems sensible to give up a few shots for less stress on the gun. Same principal says don't push the pump too hard either.