Question
in order to get enough pressure to run zone 1, i have to open the bleed screw (I think that is what it is called)on the zone 1 valve to the point where water is released at the bleed valve. When I close the bleed screw, I lose most of the pressure on zone 1, and the spray heads don't run with enough pressure. Any idea what causes this and how to fix it. Thanks!

Answer
Thanks for the question.
A valve opens based on the principle of the solenoid releasing the water pressure that is holding the valve closed. When the electricity is applied, the solenoid pulls up the plunger to release the water. That's the technical explanation, now for some useful information.
Your solenoid is probably not opening all the way. If you remove it and pull the plunger out from the center, you should be able to clean it. Try this first. There is a possibility the dump port of the valve (where the solenoid releases the water to) is partially plugged. Though you can clean the port, it is micro small and time consuming to clean. If this is the case I'd recommend replacing the valve. You actually don't need to replace the entire valve, only the top portion. It contains all of the working parts.
Hope this helps.

Matt