Hi, I installed a pegasus shower /tub valve and trim in a house I own, the model is a few years old but never used.It is supposed to be one of their higher end models with the tub/ shower switch built into the valve. Also the valve itself is more complex than I'm used to there are the shut-offs built in on each side of the diverter and also some kind of large nut on the cold side, I removed it, and its some kind of valve maybe for pressure control or something. Anyway I can't get cold water to come though the valve. I've tried everything I know to do, there is hot water and I made sure the shut-offs on the valve are open all the way, and there is cold water pressure all the way up to the valve, and I checked for any debris in the chamber. To me the only thing left has to be this "strange valve on the cold side" that I know nothing about can it be bad or stuck and obstructing the cold water? I should mention that when I turned the water on I did the cold water first and I did get a little bit of water through the shower head but it was only for about 20 seconds and then it trickled away now I can't get a drop through the cold side. Any help you can give will be great! Thanks