Pressure regulator/\unloader, wtf?

[Out of Character - 0]

I bought a new pressure regulator/unloader and for some reason it works like both?

I tested it after install and it worked fine. I set the pressure and then it would drop about a little when keying the wand.

Tonight when we started a kitchen job it was working the same as always. After a couple hours I dumped the waste and started it up again. This time I could hear the pump running but the gauge showed 0psi. One of my guys started cleaning while I was looking at the gauge and the pressure would rise only when the wand was triggered. I tried different pressures and it kept running the same way. 2 Hours later I went to shut down and dump again, it had switched back to holding pressure and dropping a little when keyed. When I started it again there was no change.

Anyone know what's up with this thing?

 

[dealtimeman]

At the momentous looked at the gauge the pump hadnt primed yet. Maybe?

 

[Shawn Forsythe]

The check valve in the unloader valve is possibly sticking. When stuck open, the unloader performs as a bypass regulator. When the valve operates normally, the unloader will unload the pump when there is no output flow (wand valve off). May only be a problem when new.

There is also the possibility that your primary orifice is worn out and trickling too much to the wastetank, thereby initiating just enough flow to trip the check valve.

A third possibility is that your unit, if equipped with a bypass water solenoid to control temperature, the action of bypassing is producing the "regulator mode" anomaly (not likely on a White Magic).

But on that White Magic, your over pressurization safety valve may be trickling sometimes. That would also do it (initiate regulator mode).

 

[Jim Martin]

..there are a few machines that require you to remove the check valve...you might want to look at the old one and confirm if there is one in there or not......

 

[Shawn Forsythe]

Most (every one in the last 15 years or so) of White Magic's Slide-in units retain the unloader function. So the check valve is used.

 

[Out of Character - 0]

Both my white magics are direct drives. I'm assuming it's the check valve since I don't have any heat control systems. The overpressure valve is removed, I use the one on the Little giant and it dumps under the van but wasn't.

It seems to work fine both ways, we'll see if it continues to change on a whim.