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Cfm’s and filters


Registered Users
Air-options.com has a formula for measuring scfm that I used to check a brand new compressor a friend had bought. It was very very close to what label said it was supposed to be.
A little bit of info - found a tag on the motor; Leland Electric Dayton Ohio . 1725rpms . According to pulley calculator I’m running 400 rpms . If I increase rpms do I increase cfm’s ? Don’t think I need a new compressor but maybe tweak this ?
Yes the CFM's would increase but I would ask that you double check your figures and seek the advice of a compressor repair man to make sure. It never hurts to ask them and they should also have a meter to check the RPM's too. Do you know the make of the pump you have?
13.5 is a little on the low side. Max capacity is 4 cfm per HP. Check the motor amps and HP rating, and with some reverse engineering, you could come up with a number to increase the speed. 400 rpm pump speed is very slow.
Don’t know pump manufacturer- can only find numbers on block and head. Pump pulley Is 56(roughly) and motor pulley is 13 - can make out 1725 rpm on motor - he told me he was going to run it slow for longevity. Takes 8 minutes and 50 seconds to fill up(80 gallons) I’ll keep looking but tag is pretty worn - I measured my RPM’s 2 different ways and came up wit the same number- 13.5 cfm


Trying to be the best me, I can be
Ok - for you guys that know old compressors - tag says it’s a Wayne 6100 series (6148H) - can’t find any specs on it on the internet
According to what I've read over the years you should be getting around 3.5 to 4 cfm per hp. That assumes it's a two stage and everything is in good shape. Like Brad says the valves are the biggest influence on whether it is putting out what it should. I don't know enough about them to tell from your pic if you have a 2 stage pump or not. Maybe it's just because your motor is very large, but the pump looks on the small side.
It’s a 2 stage and rebuilt - further digging comes up with a 3 HP motor - 14 amps at 220 so my cfm calculations are close . Oh well- I know what I have now - works good! Just a little under powered - cost me $400. I’ll put a new compressor on my wish list