faulty pressure switch help please

[oscar13]

seeing as its sunday and i have nothing to do i want to get my compressor working again
it is only a small 8/25 tiger air master turbo.
when i switch it on wuth the red button, the pressure builds up and doesnt cut out on its own, it keeps rising through the red line and then safety valve kicks in and relieves all pressure but it is still then raising pressure so i have to manually cut it out.
is there something inside the switch i can adjust?
cheers

 

[rtbcomp]

There is a spring (maybe two) with a nut or screw at its centre. Slackening this (these) will reduce the cut-out pressure.

It could very well be a punctured diaphragm though, in which case it's a new switch required.

Do you use the red knob/button to switch it off, or do you switch it off at the plug?

 

[oscar13]

i use the red on/off button.
would i slacken both or just one of the nuts?

 

[rtbcomp]

If you have two springs side by side, first check the nuts are adjusted so the springs are the same length and then adjust them both by the same amount, say a turn at a time.

 

[oscar13]

awesome cheers, and slaken them both then?

 

[rtbcomp]

yes

 

[oscar13]

there was only one screw but ive adjusted and now it shuts off at 100 psi and on at about 40.

cheers buddy

 

[rtbcomp]

That difference is a bit high, it's usually about 30.

Is there a smaller screw with triangle (delta sign) next to it? This adjusts the difference between the on & off pressures. (Hysteresis).

 

[oscar13]

no there is only the one spring on the screen, wasnt an expensive compressor tho and im not sure what it was set to to begin with.