SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

I got an email with a question about a compatibility issue, as follows

Quoted from "berisrohttis"

i just hook up a hunter pro-c with 3 xtanted modules to make 12 zones, the screen was reading p error i when ahead run a two wire 18 gage, didn't work, and i test it and was reading 6vol, i unplug it, also the valves are very old they are ones that looks like a donut that you install them in a screw, tell me if these two timers are compatible,
thank you very much

The solenoids for Imperial brass valves are an oddity. They are plenty reliable, but they are not compatible with most modern controllers. The problem is that they have such a high current draw, that controllers 'see' them as short circuits. It also happens that you cannot replace the old solenoids with a new "fits-everything" solenoid, because they were not designed with the Imperial valves in mind.

All you can do, is make a choice. Replace the Imperial valves with modern ones, or install the top-of-the-line controllers from Hunter or Rainbird, or whomever, that have the capability of powering at least three zone valves from any output terminal (because the old Imperial solenoids draw that much more current than a solenoid of today)