How to Build Pressure in a Sprinkler
- 1). Check the sprinkler head. Check for debris clogging the nozzle and the intake fitting. If there does not seem to be a problem with either, replace the sprinkler head with a new one and see if the water pressure remains poor. If the pressure remains insufficient, the problem is probably not the sprinkler head.
- 2). Check the lines leading to the sprinkler. One indication that the line is clogged or broken is if all sprinklers on the same system have sufficient pressure. If other sprinklers have adequate pressure --- before digging up the line to look for breaks or clogs --- look at the distance of the sprinkler from the pump in relation to other sprinklers. If the sprinkler with insufficient pressure is at the end of the line, the problem may be the distance the water must travel down the line. In this case, put a reducer up the line and lower diameter of the pipe to increase pressure to that particular sprinkler.
- 3). Measure the grade of the ground leading up to the sprinkler. If the water must be forced up hill to reach the sprinkler, the pressure is reduced every foot of climb. Add a back-flow preventer to the line. A back-flow preventer keeps the weight of the up hill water from reducing the pressure up the line.
- 4). Check the specifications and performance the of the pump. If all the sprinklers on the system have low water pressure, the pump may need maintenance or your system may require a bigger pump. If you do not want to replace the pump, break the system into zones with valves. This allows your pump to feed a select number of sprinklers at one time rather than all of them. If the pump is appropriate for the number of sprinklers, check the size of the waterline. If the waterline is too large for the pump --- regardless of the number of sprinklers --- the water pressure will not be up to par.
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