Pump Relay On/Off Option by Zone?

[Stewart]

We have very different problems, but I believe that we need the same solution; see

Turn off pump to backflow clean filter

My Rachio 2 is working fine, but I’m having trouble with a filter clogging. Setup is: Pond -> Pump (controlled by relay connected to ‘M’ terminal) -> Filter -> sprinkler valves. The filter has a ‘flush’ port connected to a solenoid valve that feeds back to pond. The problem is that when the flush zone runs, the pump still maintains ~20 PSI; the debris particles are pressed against the filter screen and don’t flush out. I need to turn the pump off while keeping the flush zone open, so the pre…

If we don’t see a better answer on this board, three possible solutions come to mind:

1. A script that monitors Rachio activity and modifies the Advanced Wiring setting accordingly. This could run on a local machine or in the cloud.
2. A relay that operates on specific zone(s) and breaks the connection to the pump relay.
3. As above, but using a triac, assuming that the ~1 V drop in the on state does not prevent the pump relay from operating reliably.