still blowing off

[miggymarky]

I have adjusted the cut off pressure again on my 3hp Clarke to 100psi and it still blows off for approx 30-40 seconds and then compressor starts again.is the pressure switch faulty or is there another adjustment on it.

 

[rtbcomp]

Where is the air coming from? Is it the safety valve or the unloading valve?

 

[miggymarky]

Where is the air coming from? Is it the safety valve or the unloading valve?

Dont know really,all I know how is somewhere under the pressure switch.

 

[Rig Pig]

Sounds like you need a new pressure switch then, unless you can strip it down and repair it?

 

[rtbcomp]

Don't change it yet - it's important you determine where the air is coming from.

If it's coming from the safety valve, that needs changing/fixing/adjusting.

If it's coming from the unloading valve then it's probably the non-return valve where the delivery pipe joins the tank - change or try cleaning it.

If it's coming from the body of the switch then it's probably the diaphram in the switch, in this case a new switch is required.

 

[rtbcomp]

If it doesn't start to leak air until it cuts off then it looks like the non return valve.

Before it reaches cutoff pressure disconnect the mains and then set the pressure switch to off. If it blows off continuously then the non return valve is leaking. It should give a brief blast of air.

 

[miggymarky]

If it doesn't start to leak air until it cuts off then it looks like the non return valve.

Before it reaches cutoff pressure disconnect the mains and then set the pressure switch to off. If it blows off continuously then the non return valve is leaking. It should give a brief blast of air.

Ok thanks peeps