unloader valve on lefoo lf10-4h pressure switch
lefoo lf10-4h pressure switch. I know you said why would anybody want to set their unloader valve. Well I need to mine because I turned the screw thinking I had the right adjustment well I did not. Now as compressor builds pressure motor strains then pops circuit. Cut in I believe is 85 cut out like 115 but so many screws have been turned I do not know anymore left from right up from down. Thanks KJR
Hello Kent... well, I have to admit, I'm a bit puzzled by your question/comment.
I read that you've been adjusting the cut in and cut out of your pressure switch settings by turning screws in the pressure switch... OK, I get that.
I'm not quite sure how "why would anybody want to set their unloader valve." fits with your pressure switch issue?
And, I'm wondering what makes you think that it's the cut in and cut out that's making your compressor motor strain and pop breakers.
Perhaps you would comment here with some specifics?
For instance, what is the pressure on the tank gauge when your compressor motor starts to strain? Empty the tank, close the tank drain, start the compressor, and note this pressure please.
What is the make and model of your air compressor?
How is it being powered? By that, I mean, do you plug it into a wall socket, or are you using a power bar or extension cord?
Lets start with these.
air compressor cycles on and off rapidly
When I plugged my air compressor into the 120 vac outlet, the motor starting cycling on and off in a rapid fashion. I cannot tell if it is the pressure switch or one of the capacitors.
Are you comfortable with bypassing the pressure switch, only long enough to see if the compressor runs normally? That's what I would do, to see if that would isolate the pressure switch as the problem.
Know that your air compressor will not shut off if you bypass the switch to see if the compressor will run normally, so be careful.
And if you aren't comfortable mucking about with electricity, take the compressor to a shop and ask them to.
Bypassing the switch will tell you right away if the switch is the problem if the compressor starts and runs normally with the pressure switch out of the circuit.
Pressure switch for Webster air compressor
Hi Bill, I just purchased an old Webster brand twin cylinder air compressor with a 20 gallon tank.
It has a gauge at one end of the tank to tell you what pressure is in the tank and a couple of relief valve type things on the other end.
Basically when the compressor is running it keeps compressing until about 125psi then the relief valve kicks in and vents any excessive pressure and the motor keeps running to compress more air.
Also there is no on/off switch, the only way to shut it off is to unplug from the wall.
It runs on 110V.
I would like to add a pressure regulator and a pressure cut off switch rather than have all my compressed air vented.
I've seen a combined pressure regulator/cut off switch on an old Speedaire compressor online so know they exist.
Do you have any leads on where I might find one? I have a CH nail gun I'd like to run at 90psi but have no way of regulating the compressor to that.
Richard, I don't know the compressor and have not been able to find any information on the old Webster air compressor you have.
Having said that, I can see no reason why you cannot simply run the power supply to the motor circuit through a standard pressure switch to toggle the motor on and off at the pressure switch set points.
A twin cylinder compressor will typically have a PRV in the line between the cylinders, to prevent catastrophic pressure buildup in the line should the inlet valve on the second cylinder fail closed.
I don't know about the two PRV's on the other end of the tank.
I hope someone knows the original operating ranges of this compressor to give you some idea of what the safe range is.
If the PRV's are popping off at 120 PSI, and they are not failing, then that would suggest that 120 PSI is already well into the danger zone for the compressor.
As to regulating the pressure to 90 PSI to the air tool, see the regulator page or ebook for details on what they are and what they do. A regulator is what you need for air pressure control to your air tools.
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My PC compressor flips the breaker at 120 psi
(Bothell, Wa. USA)
First, thanks for taking the time and making the effort to help all of us newbies out here.
Now, I have a PC 135 psi 6hp 25 gal upright compressor. It will run up to 120 psi and then shut off. When it shuts off, it blows the 20 amp breaker. Doesn't matter what circuit its on, I've tried 3 or 4 different circuits and it blows them all.
Of course this doesn't happen 100% of the time. Just 99.999% of the time. In other words, it has operated properly 2 or 3 times over the lifetime of my ownership (I bought it used), and I have used it often in the last 5 years or so.
From what I have read it sounds like the pressure switch is shorting, and perhaps needs to be cleaned or replaced. Can you tell me if this is true, and if so, how I go about taking it apart, cleaning, and reassembling?
Chase, yup, it could be the pressure switch, but that might be too easy.
I think you do have a short to ground when the compressor stops, and it could be the switch, but it might also be a capacitor or the motor windings themselves.
Run it again though, this time with the cover of the switch off so you can see if it arcs a whole bunch when it reaches cut out pressure.
Or, see the check the capacitor page, and start there. If they check out OK, then the least expensive next step is to change the pressure switch. I doubt that it is possible to find replacement parts for them.
You can use some compressed air to blow the switch out if you want to try that.
Be careful with the power. 240 Volts to ground through you is a sure, quick, death!