This is not a question with a simple answer, because the response depends on the type of sprinklers you are using and how they apply water.
The goal is to get 10ml of water to your lawn/garden each time they operate so different nozzles will require different run times. For example regular pop-ups can be run for around 12 minutes to apply 10mls.
Toro precision nozzles need to be left on for around 25 mins to get the same result. Then there are the MP Rotators which need 45-50 mins to deliver 10mls.
There are specs for each type of sprinkler available from the manufacturers or your retic guy can help you make sense of it. Here’s an example of how to find the answer. The chart shows that PGP needs to be on for 60 mins to apply 10ml.
The important thing is to remember that not all sprinklers deliver water at the same rate.
Firstly we need to determine what kind of sprinkler it is and what is actually broken – a standard pop-up, a gear drive or some other kind.
Here’s a brief summary of the most common problems you can expect to encounter and their solution:
a) It doesn’t spray - in this case the nozzle is most likely blocked. If you unscrew it then you take it to your local retic shop and buy a replacement.
b) It Gets Stuck – if the sprinkler doesn’t come all the way up then its likely its just old and sticky. Replace the whole sprinkler. Unscrew it and then check what size it is. Take it to the shop and get a replacement.
c) It Lacks pressure – chances are the riser at the base is broken. if it also spews water out at the base then this is the most likely problem. Unscrew it and remove the riser and replace it with a new riser.
d) It Still Lacks Pressure – check for a broken pipe somewhere
e) It is too low – clear the area around it and unscrew it. Then remove the riser and get a larger riser. Put it back in.
f) It leaks – chances are the seal is old and broken. You will need to replace it.
There is only so much that can go wrong so hopefully this covers the basics.
For help with any of these issues call Andrew on 0400044236 or email firstname.lastname@example.org
If I had to name the most common ‘fix’ I do over summer it would be replacing the risers on sprinklers that have been driven over. It happens all the time!
If you discover that your system seems to have lost some pressure on a station then look for 1 or more sprinklers with water pooling around them. The most likely place you will find these sprinklers is by the kerb as typically cars drive over them and the pressure snaps the small black poly riser that joins the sprinkler to the PVC pipe.
Unless you have a ‘riser removal tool’ you won’t be able to fix this on your own. So either give me a call or duck down to your local retic store and get one of these tools and a new riser. Be sure to check the size of riser before going as it may be longer that the standard 15mm x 25mm.
Once you’ve removed the old riser you can install the new sprinkler and riser. Be sure to flush out any sand and rubbish before inserting the nozzle otherwise you will be making another trip to the store for a new nozzle.