View Full Version : more zones wanted, no more wires

09-28-2006, 04:13 PM
i want to add more zones/valves to my existing sprinkler system, but the wires in the underground cable bringing 24V to the various valves, are all in use.

does anyone manufacture two valves that can be separately controlled via one wire? maybe ac vs. dc, or with diodes?

I hate to have to re-lay another cable.

Gary Swart
09-29-2006, 05:59 PM
You have to have a separate hot wire from the controller to each solonoid. The ground is a common wire and is daisy chained from valve to valve.

10-03-2006, 09:03 AM
You may be able to install a ground rod at the control box and at the valve sites and use only one conductor per valve, with the other side of the solonoid attached to the local ground rod.

Note... I have not tried this.


Bill Arden
10-10-2006, 02:43 AM
Do all the valves have to be on at the same time?

If not you could wire them using relay logic.

For example if valve #6 needs to be on when valve #1 is on and vave #2 is off, you could use a relay on #2 to tie valve #6's common to the common wire. #6's hot wire would then tie to the #1 hot.

Just rember to get 24V AC relays.
AC relays are different than DC ones.

Edit: With "dual throw" relays you could do even more arangements like have it so that when #4 is on #6 is controled by the #1 position with #1 always being off. Kinda of a A/B thing.

So for example using a 2 pole "dual throw" relay
Relay coil from #3 hot to common
Center of each pole is connected to #1,#2
4 valves can then be connected to the switched hots to the common.

The controler would then be programed to turn on valve #3 which would change the system from running the first two valves to the second two.

More relays and more wires and the number of valves you can run go up.

Gary Swart
10-10-2006, 07:01 AM
You have to have a separate hot wire to the solonoid on each valve. Each valve is tied or linked to the same ground wire. All of the hot wires have to come from the controller, each on their own separate post. The ground wire also comes from the controller. There's no other way to do it.

10-10-2006, 05:40 PM
please clarify

10-10-2006, 07:01 PM
Hello Gail,

Bill is correct...Here is a product that does just as he mentioned.
This may be easier to understand


Bill Arden
10-10-2006, 11:02 PM
The link divot provided is for a easier to install system where one toggleing relay is used. This means that the first time the zone is run "valve A" runs and the second time the zone is activated "valve B" runs.

What I was suggesting is more complex and would dedicate a zone just to switching which valves would be run. This would prevent the system from getting out of sequence and running the wrong valve.

Gary Swart
10-11-2006, 05:16 PM
Guess I'm not to old to learn about new products. The "Doubler" device appears to be an answer to adding zones without additional wiring.