Greywater System Scheduling

I am setting up a grey water system for my home, an now I’m trying to figure out how to schedule the irrigation. I have 12 drip zones, each on a fixed schedule throughout the week, during times when we wash clothes or shower. These essentially open up the valve, and allow any greywater produced to drip onto the plants. I’m finding that we don’t produce enough greywater to water the plans during the summer months.

To get enough water to the plants during the summer months, I want to schedule 1-3min of city water on a fixed schedule to run when the valves from the above are open. How do I do this? Do I need to be another Rachio controller to schedule the 1-3min of city water? Is this where “relays” would work?

@sbuswell - I can think of a couple of ways to accomplish this, but I’m concerned about plumbing code issues and cross-contamination of the public water supply with the grey water system without knowing how things are connected, etc.

The grey water goes into a grey tank with a float pump. When it becomes full, it pumps the water out to through the open valves which are controlled buy the Rachio schedule. City Water is scheduled (1-3min), pushing water into the same grey water tank as above and out through the same valves. Does that help clarify how things are connected?

@sbuswell - so I’m assuming there is an air gap between the City Water outlet and the top of the grey water tank to prevent cross contamination.

One option would be to use zone 13 to run the City Water into the tank. Have it ordered first in the run or a separate schedule that runs 5 minutes before the actual irrigation run. You might need to protect from an over-filling situation, like with a high level float to break the connection with the City Water solenoid.

Another option would be to use the Master Valve output and a low level float in the grey water tank. As the master valve is energized when Rachio is calling for water, running that lead through the low level float (open when high, closed when low) to the City Water valve would supply City Water whenever the irrigation system is running and there isn’t enough grey water. This valve’s set point should be just above the point where the grey water pump would shut off due to low water.