See my Sprinker solenoid woes

The home I am currently living in and own had a garden irrigation system install with bore pump when purchased. The system was over 20 years old when I purchased and is now over 30 years old.

Some problems when purchased:

• The location of the sprinkler control valves was unknown. Of the 8 station control valves, one valve was well underground, 3 were mostly underground and the remaining reasonably obvious to see the cover above ground.
• The location of the pump was unknown. Fortunately the neighbor seen the bore installed and told me where it approximately was, and it was then easily found with a large plastic cover lid only covered with about 20mm of soil.
• The previous owner(s) had placed trees close to or on top of the various valves. To make matters worse some of the plant were inappropriate for an urban block, e.g. large ficus trees. I had the ficus trees removed. These trees and plants not only caused damage to the sprinklers, but also to the fences and retaining wall. To make matters worse many trees and plants we place too close to the fences and retaining walls. I rough rule is minimum 600mm for any tree and larger trees add the final diameter of the trunk to 600mm.
• The previous owner(s) had already modified and repaired the piping and control valve wiring to allow for the overgrown plants and trees.
• The control valve wiring only used old fashion car crimp fittings. The fittings and wiring was corroded from being in wet soil.

Changes I made over the past 10 years or so:

• I replaced the old manual controller with an Opensprinkler sprinkler controller. The version I am using is V2.1 from memory, not the current later version for sale. Interestingly the older version comes with ethernet built-in and no built in wifi. The new version has wifi built in and ethernet as an optional extra. I had my house wire with ethernet cable in 2014, and included a cable to the sprinkler system location. I only fitted 7 stations to the controler as this is all the new controller allowed without an extension board. One of my control stations had a hose connection only that was not used.
• I ended up replacing all the wiring to to the various control stations. The wiring was a nightmare over a number of years. After patching and making working I ended up replacing all.
  • Recommended residential wiring is 0.5mm². This is supposedly good for remote valves up to 100m distant. This is horrible thin wire. Care needs to be taken when installing not to damage. I would prefer not to use less than 1mm² wire or even 1.5mm²simply as it is more durable. The original wiring was defiantly greater than 0.5mm²! Some of the original wiring was also single core wire, not multistrand.
• I replaced control valves as I started having problems with them. Currently I have replaced 3 of the 8 station control valves. The original 5 valves are still operating after 30 years.
  • The original valves look to be Hardy Century Plus model that is not longer sold. A similar model is the Irritrol (Toro) Century Plus Series which is sold as a commercial product at about 4x the price of a residential valve.
  • I had installed an Irritrol 2500MT jar top solenoid that gave me no end of problems. I replaced the valve solenoid 3 time as it went open circuit and then replaced the entire valve! No other valves I used had open circuit solenoid problems. I will not purchase Irritrol valves again!
  • The current valve I am using is the K-rain Pro series 150, specifically model 7101-BSP Pro series 150 1: valve. (Not a jar top!)

The automatic system requires constant monitoring to ensure correct operation:

1. The station valves are operating correctly
2. The sprinklers or their upstream strainers are not blocked
3. The pump and wiring are working correctly. I had a problem with loose wiring on the control relay and overload that damaged this equipment. A replacement relay and overload can cost a few hundred dollars.

If these checks are not made the garden will suffer, particularly in the warmer dryer summer months.

The urban area I live in only allows automatic garden irrigation on 2 days per week. It used to be 3 days a week for those with bores, but this was restricted to 2 days a week starting in 2022. Hand irrigation is allowed at any time. In the hot summer months 2 days a week is not enough irrigation frequency to allow healthy plant development for non-tolerant type plants. Automatic irrigation during the day heat is not allowed. Automatic irrigation is not allowed in the wetter winter months.

I have the automatic system set-up to irrigate in the early morning. I usually short cycle through on a fix time on each irrigation station to 'wet' the soil and then another longer variable cycle to soak the soil. The controller adjusts the variable time with a factor based upon the past measured weather temperature and precipitation, this factor can vary from 0 - 200%, this is another reason I like the fix wetting time irrigation, to ensure some irrigation occurs.

Micro-sprays are rated at 150kPa and spray nozzles a bit higher at 2 - 3 bar. Often the micro sprays are attached via a 4mm poly tube, but also directly into larger 13mm or 19mm pipe.

I recommend only using pop-ups where required, that is for underground application. Permanent above ground installation should use brush heads or micro sprays. I prefer standardise on female nozzles. I also use these on the brush heads with adapters. I always try to use a strainer element installed just below the spray nozzle. The strainer elements also block up slowly, but tend to give more reliable performance than without. I prefer to use 100mm pup-ups where possible to ensure the nozzle raise well above the nominal ground level. However I also use 80mm and 50mm (standard) pop-ups where installation requires. My current preferred pop-up is K-Rain Flush cap Pro-S series that comes in 50mm, 800mm and 100m pop up sizes. I prefer the use of fixed spray nozzles instead of adjustable nozzles. They are easier to use and more reliable. I only use adjustable now where I want a narrow spray.

The angle and radius nozzle configuration can vary. e.g. 90° 3.7m radius.

I use brush head adapters mounted on 15mm ploy risers. I use standard female fixed spray nozzles with nozzle strainers, the same as used on pop-ups.

I generally use the Pope 90° (60Lph @ 150kPa), 180° (80Lph @ 150kPa) and 360° (110Lph @ 150kPa) spray jet nozzles. These have a 1m radius throw and rated flow rate of 60-110Lph. If I want higher flow rate from these nozzles I have on occasion drilled our the ports to 1.5mm or 2mm diameter.