Claber 8410 Aquadue Duplo Water Time

I’m trying to successfully irrigate a pot garden with over 200 pots of different sizes, pots get hotter and dry out quicker than ground borders, and smaller ones dry out quicker still. This is a challenge for any single irrigation type and I had to use a combined delivery system of sprinklers, sprays, misters and drippers to ensure good distribution without water logging or wasting water.

Adding more sprays or drippers as the wife added pots or rearranged the layout became too much for the first system controlled by the HL tap timer, each change caused the whole system to loose range, the misters just spattered and drippers had such a varied delivery that I decided to divide the circuit into 2 zones, with their own timers, halving the individual flow requirements and regaining effective delivery performances.

I browsed and found the Duplo timer, with two independent outlets, which are controlled so that only one can run at a time. This has overcome both domestic water supply limitation and irrigation demand in one go. Two independent lines are being set up by cutting the existing irrigation pipe at about Half way around, plugging the ends and extending the old end back to the timer. I’ve set up so that most of the pots on Line A; receive a suitable supply, the improved delivery also allowed me to simplify by removing a few drippers (the others are being replaced by the Claber adjustable items). I’m currently extending the original pipe end back to the spare timer outlet to complete line B, whilst including some more delivery points. so that the whole garden will survive summer.

This is an early review, and so-far, I’ve encountered two difficulties.

The first is a problem not with the timer, but with my existing delivery pipework, which was adequate for the lesser brand (HL), this may affect others who upgrade too. The line outlets from this Claber timer are not pressure regulated, which dramatically improves performance, the higher flow-rate and pressure has caused the existing HL pipe to pop off the connectors in a few locations during partial setup (there was less delivery flow, which increases back pressure). Simply Adding additional clips around the pipe at the tee’s, elbows etc has overcome this. Fitting pressure regulators to the timer outlet may prevent this at the expense of reduced flow. The Claber tees and elbows are of slightly larger diameter than my original system and are a tight fit without the need for clips, but they are expensive.

Update- Balancing flow on line A, which tee’s off in 2 directions, one with less demand, needed some control. Using simple shut off valves limits both flow and pressure after the valve but this varies due to fluctuating water main supply line pressure. I found that using a pair of Rain Bird in-line pressure regulators designed for 3/4 inch lines provided good pressure control and plenty of flow rate, these are available with a range of preset pressures and require reducing adapters to suit the line being used.

The other difficulty is with the unit. Setup and later adjustment is less than intuitive. The instructions need to be kept at hand, but those included are multi-lingual, difficult to follow and reduced in depth of information, eg there are no instructions on modifying or deleting programs. The company have much better, single language PDF versions with all the required info available in on their web site.

Follow-up Aug 2019
I noticed a small, continually damp area on the flags beneath the timer, the flags became a little green and the leak was found to be from the supply tap screw connector on the top of the unit. I replaced the seals, but there is still a slight leak. I noticed replacement tap connectors are available. I’ll first try it on another tap to isolate the leak. I replaced the tap connectors, seal and 0-ring ring; the leak continued.

Follow-Up Spring 2020
Broke it out for spring, the leak started making the flags wet again.. There appears to be a tiny crack in the threaded neck of the timer housing onto which the large tap supply connector screws, this neck joins the main housing with a sharp 90deg corner without a radius, this is known in many engineering areas as a “stress raiser”.

I don’t want to buy another unit, that’s why I steer away from HL…
I wonder if Claber will provide a replacement? Update to follow.

Repaired..
contacting Claber UK lead to them supplying a replacement rear case and outlet moulding. Components transferred easily and all is dry.