Aerobic system alarm going off — what does it mean and what should I check first?

An alarm on an aerobic treatment unit generally signals either a high-water condition — caused by a "plugged distribution head, plugged filters, broken pump, excessive water use, [or] broken fixtures" — or a low-air-pressure condition caused by a "broken air pump, broken air lines, [or] low water level in the aeration chamber" (Texas A&M AgriLife Extension, L-5302 Aerobic Treatment Unit). AgriLife's instruction is to call your maintenance provider and "reduce nonessential water use in the home until the system is fixed" (AgriLife L-5302). Waller County adds the first homeowner check: "check your breakers to make sure power is getting to your system," and if breakers are fine, "call your service provider immediately"; the mute button silences the buzzer only — "anytime you mute the alarm, you should call your septic maintenance company" (Waller County).

Reviewed August 2026. Links go to the sources this answer was checked against.