That alarm is wired to one job: warn you before sewage has nowhere to go. It means the water level in a pump chamber has climbed too high — so don’t just mute it and move on.
Most often the effluent pump has failed or a float switch is stuck, and the chamber is filling. You usually have a short window — a few hours to a day of careful water use — before it backs up.
Cut your water use right down and call an operator. A failed pump or float is a routine repair if you catch it on the alarm rather than on the backup.
Acreage Septic connects you with a vetted local operator who works your grid roads. Pick your area to get local pricing and call: