Aquamist adjustable pressure switch - which way?

[JohnA]

If I turn the screw clockwise what happens to the trigger pressure?
Does it go higher or lower?

Also roughly how sensitive is it? Say half a turn would relate to how many psi?

I've got the System 1s by the way

thanks in advance

[Forum Admin]

The boost pressure switch is normally closed and the circuit opens when the reference pressure is reached on the 1s this engages the pump.

Turning clockwise increases the amount of pressure necessary to open the circuit. Turning counter clockwise decreases the amount of pressure necessary to open the circuit.

I do not know the calibration from turns to psi.

[JohnA]

Thanks, TurboICE

I'm not convinced it works properly, as I haven't got an LED on the dash.
I was hoping to feel the difference from the engine running differently, but no such luck. The level on the washer bottle doesn't move either, and that makes me think!

There are water bubbles in the high-pressure water pipe, so something's working at least.

Is the pump really noisy and vibrating when it operates, or is it silent as a mouse? I haven't seen it running on a dyno yet, so I can't tell from the inside of the cabin while it's doing 20psi!

[Forum Admin]

The switch is sensitive to heat, is it in a hot area?

A quick way to test the switch functioning (but not the pressure to trigger) would be to put an ohm meter across the two terminals, in its normal state the resistance should be low to zero. Now disconnect the hose from the pressure reference - using a syringe with a plastic tip that fits the hose, put the tip in the hose so that it won't leak, start with the plunger pulled back and push the plunger forward. If the ohm meter goes infinite then the switch is working though as I said you still don't know at what pressure.

No to make sure your circuits are good connect the wires back to the switch, with the jet removed from the engine and in a container - do the same thing with the syringe in the hose this time with the ignition in the on position but the engine not running. You should get water flow as long as there is pressure on the switch - i.e. no leaks from the syringe.

BTW - what are you using as the pressure reference for your switch?

[JohnA]

The switch is sensitive to heat, is it in a hot area?Not particularly, no

A quick way to test the switch functioning (but not the pressure to trigger) would be to put an ohm meter across the two terminals, in its normal state the resistance should be low to zero. ..
Did that, also ignition on/ pressure switch disconnected: the pump ran.
Very noisy - is it supposed to be so noisy? Gee...

BTW - what are you using as the pressure reference for your switch?
The boost gauge.
I can hear (and feel) the pump running, it vibrates big time!

I played with the screw a bit, and it was set from the factory at around 1 bar, depsite the documentation saying it was set at 10psi!