Basic Compressor Setup?

[busastars]

Here is a simple question, sounds stupid as most of my questions BUT you all should know how simple I am by now

I am buying another compressor but before I sell my old one I was just wondering how do you set them up and play with them. I have used air line tools for years but all I have ever done is plug & play. So guess I should ask the basic questions.

On this little compressor it has two gauges, first one reads around 30psi second one around 90psi, drops to about 60psi then starts running.

I'm guessing the second gauge being 90psi is what comes out of the hose BUT why does the first one only show 30psi, what does this mean.

Also the only adjustment I can see is the red screw cap, does not seem to do much, is there any other way of adjusting this little compressor, maybe under the cover of the switch or something like that?

Keep it simple please as I can be a little stupid.

 

[rikrobson]

The Gauge on the left looks to be the tank pressure and the right hand one the output, regulated pressure.
The left one will always be reading a higher pressure then the right one.
I suspect that one on the gauges id not working. and the red knob is the regulator so this should affect the right-hand gauge.

If you empty the tank then they should both read zero. if not thee the gauge that is still giving a reading has gone u/s

If you charge the tank then the LH gauge should climb to around 100 psi then the compressor cut out. the red knob should then be adjusting the output.

 

[Country Joe]

Hi there,
On mine, the red screw cap would be used to set the pressure at the hose outlet.
If you turn it down, it hisses as it lets air out, and the gauge would drop to show a lower pressure. The one on the left is the pressure in the receiver, and when that drops down enough (to about 100 psi - on mine) the motor kicks in, until it reaches about 150 psi, then stops.
If you turned it on now, the motor would start, and the one that reads 30 psi, would keep rising, until the upper pressure is reached, and then stop automatically.

I've just tried to replicate your dials on mine, but as the receiver pressure drops, so does the gauge for the outlet. (I can't make the outlet show a higher pressure than the receiver - thought I'd be able to, but couldn't)
The red control on yours should still be able to turn the pressure down at the outlet, though. I would expect to hear the escaping air as it's being turned down. (I would expect you to have to turn the red thing anti-clockwise to do this)
I'm guessing that if it does nothing, it could be stuck at 90 psi. If the outlet control (red thing) is turned a long way up, it might take a couple of turns before you hear a hiss or see anything happen.
I'm assuming it does switch on?

All the Best,
CJ
PS - Oops, too slow at typing!

 

[tigler]

The above replies are correct, the large gauge is for receiver pressure and the smaller gauge is for regulated output pressure, adjustable by the red knob. You should be able to set the required output pressure by turning the red knob, normally turning clockwise increases pressure, anti clock for lower pressure. Lifting it, or possibly pushing it down should lock it. If the receiver gauge never reads above 30 PSI then it is duff, fit a new one, available for pennies on ebay etc. You need a back feed type, more than likely a 1/8" NPT or BSP thread, either will do, they are almost the same in that size.

 

[busastars]

That's ok, just thought it was a little odd where the one gauge read lower. Not bothered about changing it as I should have another compressor soon and this one will just go on ebay for a few pounds. Unless anyone here is local and looking for a cheep compressor.

 

[Faaluke]

If you have the room you could always keep it as a spare. Get a big job and plumb them together for bigger capacity etc :P