First, you have to figure out what is causing the low
pressure...check for leaks. You are
looking for a major leak which may manifest itself by way of a vigorous spray
that is obvious or by way of a large leak that can sometimes be less obvious. Large pvc leaks can be less obvious because
they do not emit water at as high of a pressure so the water more gently flows
out of the breach as opposed to spraying out of the break. If the location of the leak is not evident,
one way to find it is to either cap off the heads or turn the heads off at the
head (this is a feature of The Newer RainBird Sprinkler Heads). By capping off the heads, you then send all
of the available pressure to the weakest point which is the water main leak you
are looking for. This additional
pressure will hopefully make the leak more evident.
One cause for low "output" which can sometimes
be perceived as a low pressure situation is trash or sludge in the pvc pipes,
the valves, or at the head. Before the gunk gets to the nozzle, though, there
are small filters that can be cleaned out or replaced to achieve better spray
flow:
Another cause for low pressure on a lawn irrigation
system zone is having too many heads on a zone.
Zones are only rated for a finite number of heads. You can only use as many sprinkler heads as
your pressure and water volume will accommodate. These factors should be taken into account
when designing the layout of the system.
If there have already been heads erroneously installed (too many to a
zone), one option would be to reduce the amount of water that is emitted by
changing the spray nozzle to a lower gpm rate nozzle. For instance, you may be able to get away
with replacing a 2.5gpm nozzle with a 1.5gpm nozzle. In regards to popup spray heads, there is an
option for a water saving nozzle. Below
is a video showing how water saving nozzles work - enjoy!
