Tuesday, January 24, 2012

New video online! – mechanical timers 101

I recently produced a video for the Urban Conservation Unit. The focus of this new piece is teaching the uninitiated the ins and outs of the mechanical irrigation timer.

Ye olde time keeper

Whether on well-water or city water, 70% of the homeowner landscape irrigation systems we assess in Miami-Dade County are outfitted with a mechanical timer. Though AC-powered, these timers are as streamlined as possible...

...keeping time and day information through the use of pins and wheels, and turning on and off based on where pins are fixed and how many pins are attached in sequence.

Partners in crime

The gruesome twosome

Because all this device can do is send water and stop it, it is paired with the indexing valve in order to distribute water throughout an irrigation system’s different zones.

Exhibit A

Sworn enemy of the UCU, the indexing valve is an inefficient, unreliable and restrictive method for distributing water on a property. Does this make the mechanical timer guilty by association? Discuss among yourselves.

Carne de perro!

Despite its shortcomings, the mechanical timer does have some saving graces. First, it is built to last. Comparing it to a digital timer, one local contractor confessed to us he prefers the mechanical because it is like “carne de perro!” (tough as dog meat!).

AC power in/AC power out

Further, because many South Florida irrigation systems use pumps, the mechanical timer is advantageous because it can send 240V, or 120V, directly from the breaker to the pump – where a low-voltage digital timer requires a pump start relay.

However popular or practical, the truth about this mechanical beast is that few homeowners know how it works and even fewer know how to program it. Therein lies the motivation for producing this new video.

See it here!


  1. Great video!! I think this will be very useful!! There are many people who do not know how to set these. I have already sent it to my mom!

  2. Wow great.. it is very useful.
    The distribution of water can be done very effectively.

    ac intallations miami