Pressure on the Priority Valve????

[Hoosier]

OK...Another newbie question...




I completed my 2nd chamber project (that I know of).
So, my fill station is like this as you may remember,

Compressor-2nd chamber (Priority Valve 2200 psi)-LF Hyper Filter (Priority Valve 2200 psi: I think)-Whip Pressure Gauge-Tank

The pressure gauges on each chamber are located right before the priority valve.
Priority valve (back pressure valve): The air won’t flow out under the set up pressure.

When I fill my tank, I can see the pressure drops below the set up pressure on LF Hyper Filter. The air keeps flowing without reaching the set up point.


The pressure never drop on 2nd chamber no matter what the pressure on the tank I have, but the pressure on LF drops as same as the whip pressure gauge shows.

However, when I disconnect the whip from the tank and see from what pressure air starts to flow, it is 2200 psi.


Do I miss something?

 

[pescador775]

Maybe the #2 backpressure valve is stuck open.

 

[skippy31]

Is the priority valve not the same thing as a back pressure valve?

If so then you only need one after all the filters. At least that's how I understand it...

Skippy31

 

[Hoosier]

You are absolutely right...

However, my design is to have an independant chamber respectively. So, depending on my need, I can save(un-use) the final LF appliance...

 

[skippy31]

OK I think I understand now. OK only suggestion I can offer is to look at the flow rates. The LF filter (I used to own one) does have it's own back pressure valve and check valves. It also has a flow restrictor that is set to 6CFM (if I remember right).

If the compressor is smaller than 6CFM and you have both priority valves set to the same pressure then you may well see pressure fluctuations on the LF appliance.

Keep in mind that the priority valve will hold a pre-set pressure but they will begin to flow at a somewhat lower pressure even if they do have allow full flow.

Skippy31

 

[rjack321]

Do you have the 2nd gauge mounted on the 2nd backpressure valve? Here's pic of my setup to explain...

Gas flows into the chamber via the hose on the left.
Through gold colored backpressure reg
Continues out through coiled SS tube up and right

The gauge with the blue rubber around it (partially blocking the view of the gold anodized backpressure valve) is AFTER the actual valve in the gas flow. I have no gauge before to check the backpressure reg setting. I have roughly checked its setting by closing all the whips and seeing what they pressurize to once I hear the valve open.

 

[Hoosier]

Richard,

The pressure gauge on LF (3rd chamber) is located on the right before the priority valve. I have a whip guage on the hose to the tank...

So, I can compare the pressure before and after the final priority valve.

But, it is identical. That's my question. Why?

 

[rcontrera]

OK ... now it makes sense!

That gauge is reading the pressure after the priority valve (there are two outlets on the valve and one inlet) so, yeah ... it will be the same as the hose pressure. If you want pressure of the filter housing, you need to put the gauge BEFORE the priority valve.

Hope that helps!

 

[Hoosier]

OK ... now it makes sense!

That gauge is reading the pressure after the priority valve (there are two outlets on the valve and one inlet) so, yeah ... it will be the same as the hose pressure. If you want pressure of the filter housing, you need to put the gauge BEFORE the priority valve.

Hope that helps!

Ray.... I might not be clear so far..

I have two gagues before and after the priority valves on LF appliance. My question is why the pressure on two gauges are the same when I fill the tank?

For example, if I set up the pressure (2000 psi) on the gauge BEFORE the Priority valve(Let's call it "Gauge A"), the pressure reading on Gauge A shoud not go down below 2000 psi when I fill the tank (no matter what pressure the tank has). Am I right? Because no air comes out below 2000 psi from the filter housing.

The gauge after the Priority valve (Gauge B) shows the tank pressure whatever it is...

The Gauge A is placed before the Priority valve, NOT on the other outlet of the Priority valve.

 

[rcontrera]

Oh, OK. Yeah ... stuck priority valve. You can download the maintenance instructions HERE and do a quick cleaning.

Good luck!!