Sprinkler System: Only working at 50% to 75%. Can you backing me get the message why? When my sprinkler system comes on, it seems to be working at...

When my sprinkler system comes on, it seems to be working at the 50% to 75% level. I be watching one zone for about 5 minutes spray water moderately, and next the zone started to "sputter" a little. After the "sputter", the system quickly started spraying farther out and much more hose down thereafter. This has happened contained by other zones, too. I checked another zone tonight for 10 minutes, but it never "sputtered" or sprayed more water and thus merely worked at 50% to 75%. Can you tell me why this is happening and how to fix it?
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Answers:    it depends how various heads (sprayers) are connected to each solenoid. I own one solenoid with three sprayers, and another solenoid with seven which one you ruminate has more pressure? ofcoarse is the one with smaller quantity sprayers. Look into that too. Otherwise if you have the same amount of sprayers on respectively solenoid. then you have a hose leak in the system.
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Could in that be some debris in the lines? If dirt get into the pipes it could clog them making them less effective. You can try flushing the system. Identify the terminal sprinkler on respectively zone. Remove the spray nozzle and run the zone. This should help evacuate any dirt or clog. Make sure you run the zones within from closest to furthest from the water source (water main).

It might also be worth checking each nozzle to generate sure the filters aren't clogged.

Worst case scenario is that you hold a leak somewhere. This can happen as the pipes age. The PVC become more brittle as time goes by and can eventually wear lose or develop a leak, especially at the connections. Watch for dampen pooling in your yard or a subdivision of your yard becoming overly saturated when the sprinkler system runs.