Hi folks,
I moved into a house with existing sprinkler system. It has 6 zones and the house is roughly 5 years old. I believe the owner have the system installed when the house was first built, and last year when we bought the house, the system had already been turned on (we bought the house in August.)

I had a company to winterized the system for me. Now it is Spring, I plan on turned the system on fairly soon but want your advice first before I turn it on myself. I noticed the pipes outside where the sprinkler system sits has 2 screws hat is perpendicular. Do I need to turn that on horizontal before I turn the main valve on in my basement? Or it is ok to not touch that?

I want to properly turn on the system and prevent any blow outs of the sprinkler heads or the pipes. I am new to this so a step by step instruction is greatly appreciated!

I find this site very helpful and any insight will be carefully learned