Question
QUESTION: My neighbor is having work done in the bathrooms and had to turn the water off. When the water was turned back on everything but the sprinklers worked. He asked me if I could help but I know nothing about sprinklers or how they work. We need help. That's why I'm Here. Can you help us?

ANSWER: I need a little more info. What kind of work was being preformed in the bathroom? If it was plumbing, it appears the water service pipe to the irrigation was disconnected. Or the valve was shut-off and not turned back on.
If you have and air compressor try to connect it to your backflow preventer or on the irrigation mainline close to where it exit the house. You should be able to hear air flowing or water gurgling. Be cautious though. If the pipe was cut off and still open, you could be pushing water back into the house.
If you can provide a little more info, I think we can resolve this one.



---------- FOLLOW-UP ----------

QUESTION: Thanks for the response. Yes plumbing was involved, they are installing new tub and risers. Yesterday he used the hose and had no problems,says all the air was purged inside the house. We opened the valve and checked the controller, everything was fine. As for the backflow preventer, is this the thing that has the filter in it? If so, do I take the filter out and through there put the air hose to do what you suggested?

ANSWER: It appears, yesterday you established the water was getting out of the home to the hose connection. You mention a filter, indicating the water has sediment in it. Any work on the pipe inside the home could dislodge more sediment. Is it possible it is plugged? Have you located the electric irrigation valve/ valves and tried to manually open them? To manually open an electric valve, look on the top of the valve for a small knob. Turn it counterclockwise about 1- 1-1/2 turns. If it doesn't have this knob, then turn the solenoid (the thing with the wires into it) counterclockwise about 1 to 1-1/2 turns. Be careful not to completely unscrew the solenoid. If the irrigation come on, then we've establish the water is to the valves.  
The backflow preventer is generally a brass apparatus located just outside the home. It stop the irrigation water from getting back into the home. It is possible you don't have one. Hold up on the air compressor for right now.

---------- FOLLOW-UP ----------

QUESTION: Again, thanks for the quick response. I did as you suggested with the valves and still no water. We then turned the hose on and closed the main valve. Sure enough the water stopped flowing. Then we opened the valve again and closed and opened the valve on the part of the pipe that u's down to supply the irrigation system. From there down we got no water. So it looks as if that valve is clogged. Right under that valve is where the filter is and when I unscrewed the end I expected water to come out but got nothing. So unless I'm reading this wrong, that's the problem. What do you think?

Answer
Yes, I think you've found the problem. Sometimes when plumbing is changed in a home the scale inside the pipes gets shaken loose. Unfortunately, it ended up in the irrigation. If you can remove the connection with the valve. Try soaking it in vinegar overnight. If you don't want to wait that long, you can use toilet bowl cleaner. Obviously, use all the proper precautions with the cleaner, it is a strong acid and will burn your skin. The vineger method is safer. Good luck!