Hard to tell how you have it plumbed with the Hose at the top of the picture, as well as the hose on the left, going out of the pic. It looks to me you are running pressure into the valve on the left side first, and them looping a hose from the PB back to the valve on the right, pressure port. The return from the valve on the right is looped from the rightside valve and connected to the return on the leftside valve, by a tee and then the hose loops out of pic back to the return filter. This should work, but kind of looks like a roundabout way to get there. Not knowing exactly what or why you plumbed things the way you did, I would probably plumb the pressure line into the valve on the right side first, then use a short hose to connect the right side valve PB port to the Pressure port of the left side valve. The return from the first valve, I would probably just run straight to a tee at the filter and also run the return from the second valve to the opposite side of the same tee. I think that would shorthen the hose runs and maybe make the plumbing a little neater without all those looping hoses. Nothing wrong with teeing the return lines together and you do need one return for each valve. Unless you have another line running to the filter that is not in the pic, then things should work the way it is currently plumbed.