Jandy RS-485 Wiring Conflicts


New member
Jul 25, 2014
I have an RS12 with a secondary Power Panel. The Secondary Panel, Aquapure 1400, Indoor Controller, and Spa Link were all connected to a Jandy Multiplexer (with lightning board) and then connected to one of the 2 RS_485 4 pin connecters on the RS motherboard. Went to add an IQ900 iAqualink and use the other RS-485 connector. Now, while the Aquapure is functional, it will not appear on the iAqualink. If I disconnect the Spa Link, then the Aquapure appears. I have tried doubling up on the terminals and relocating the devices on the multiplexer to no solution. Jandy, as usual, will not speak to homeowners about such things. What is the wiring conflict and any solutions?

Bama Rambler

Mod Squad
TFP Expert
Bronze Supporter
LifeTime Supporter
Jun 22, 2009
SouthWest Alabama
Assuming that the second RS-485 connector is just a drop on the network. It sounds like you either have conflicting addresses or you're exceeding the maximum number of devices on the network that Jandy allows. What happens if you drop one of the other devices off the network?


TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
There are some obvious things that are still worth double checking. You need to be careful not to cause any shorts when connecting up multiple devices. It is also important to get the correct wire to the correct terminal. These are so obvious that they often go without saying, but that are fairly easy mistakes to make, so worth an extra check.