Problem with filter bypass

[BlackCap]

Can anybody help? I have a problem with my Marchisio 20 cm filter when I use the bypass. The pressure shoots up to 25 psi immediately even though I’m using plain water.

 

[stickman]

It doesn't look like you have the filter set up correctly. This manual may help if you don't already have one.

 

[BlackCap]

I have the manual. To me it looks correct. I’m scratching my head.

The way I see it: product comes in on the left, migrates right, goes through the hole in the bypass on the right, then migrates to the left and exits the rear.

 

[stickman]

It looks like you have the filter set up for dual filtration. The plate in the center is the divider plate, this allows the filter to be divided into two sections. For each section the filter sheets operate in parallel, so the first section in your setup has 4 sheets which will increase the pressure drop accordingly. The chart on page 11 in the manual indicates for various filter sheets the required pressure to achieve the rated flow in liters per hour, but note it is based on 10 sheets. In your case, the first section limits the filter capacity, so you need to multiply the rated flow by .4 (4 sheets/10 sheets). Take the polishing sheets as an example, the pressure given is 2 Kg/cm2 which is approximately 28psi to achieve 350 L/hr, but with 4 sheets at 28psi the flow will be 140 L/hr.