Info, impact, causes, and troubleshooting a "Zone Shutdown Low Flow Variance" message.
Common Causes
- Plugged sprinkler heads on.
- A restriction at the zone valve.
- Incorrect learned flow value for a zone.
What happens now? From the alert message:
- Zone 13 experienced lower than expected flow and was shutdown.
- Flow Variance Threshold (measured in %) is set to allow 30% variance but controller detected a 45.1% variance.
- Expected vs Actual Flow (measured in Gallons per Minute (GPM)). The controller expected a flow of 40 GPM but only measured 23 GPM.
Troubleshooting
- Check for clogged or damaged sprinkler heads.
- Inspect the zone valve for any restrictions.
- If you suspect the learned flow value is inaccurate, you can relearn the flow for that specific zone.
- If needed, consider opting out of low flow shutdowns using Advanced Flow Variance.
- Allowing the zone to apply some water rather than shutting it off completely may be more beneficial. You can configure the controller to shut down for high flow issues, while not shutting down low flow, so it can send alerts.
Finding Learn Flow
- Finding previously learned flow go into BaseManager → values can be found → Zone Assignment section.
- Either at controller or through BaseManager’s Live View → Zone Flow or Program Learn Flow, if applicable.
- BaseManager Maps by selecting Learn Flow for an individual zone.