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When a septic alarm sounds, limit water use and check for a tripped breaker before you call anyone. Alarms on pumps and filters must be attended to immediately Source 2: UMN Septic Care and Maintenance. Texas code puts an electrical alarm on a circuit separate from the pump's Source 1: TCEQ 30 TAC Chapter 285.
This guide works through five possible causes in order: breaker, water use, effluent filter, float switch, and pump or blower.
You can look at the breaker panel, limit water use, and clean a homeowner-maintained effluent filter. Resetting a breaker, a float switch, and a failed pump or blower are for a licensed professional. Never go into the tank.
Two different alarms, and why the wiring matters
Homeowners routinely assume one alarm means one thing, and a septic system can carry two. A pump-equipped system, including an aerobic treatment unit, must carry an audible and visible high-water alarm on its pump tank Source 1: TCEQ 30 TAC Chapter 285. A gravity system with no pump has no such requirement. It may still carry a second, unrelated alarm on its effluent filter, the screen that catches solids at the tank's outlet Source 2: UMN Septic Care and Maintenance.
Which one you have decides which of the five causes below are even possible. A gravity system with no pump has no pump-failure branch.
The wiring behind a pump-tank alarm is deliberate, and it is the fact this guide's first step depends on. Texas rule requires the alarm's power circuit to be separate from the pump's Source 1: TCEQ 30 TAC Chapter 285. Washington's health department says the same of the alarm and the pump Source 4: Washington State Department of Health, DOH 337-087. So look at both circuits, not one.
A dual-pump system adds one wrinkle worth knowing. Texas code requires the alarm to lock on, staying lit after the second pump draws the level down Source 1: TCEQ 30 TAC Chapter 285.
The EPA names the high-water alarm as a sign to watch for on pump systems Source 3: EPA Tribal SepticSmart Homeowner's Guide, and UMN counts checking pumps and alarms for proper function as ordinary monitoring Source 2: UMN Septic Care and Maintenance.
Five causes, cheapest and safest first
Work down the list and stop where the guide says stop. Nothing below requires going into the tank.
Look at the breaker panel for a tripped breaker. A tripped circuit breaker is the first thing Washington's health department lists to check before calling for service. Texas code puts an electrical alarm on a circuit separate from the pump's, so there are two circuits to look at.
Look and note what you see. Turn off the power at the breaker and unplug all cords before handling the pump or floats. Have a licensed electrician or septic pro reset a tripped breaker.
Limit your water use while the alarm is on. Excessive water use is one possible cause. Avoiding baths, showers and clothes washing buys time to get the problem corrected. Alarms on pumps and filters must be attended to immediately.
Check the effluent filter, if your system has one. A gravity system's effluent filter sits on the outlet pipe and can carry its own alarm, separate from a pump tank's high-water alarm. Some effluent filters are maintained by the homeowner and some by your pumper; check which yours is.
Never go into the septic tank. If your filter is the pumper-maintained type, or you cannot reach it without going into the tank, leave it to your pumper or a septic professional.
Do not reach into the tank to check the float switch. Washington's health department lists tangled control floats among the possible causes and says to turn the power off at the breaker and unplug all cords before handling floats. Have a licensed electrician or septic pro check the float.
Never go into the septic tank: it lacks oxygen and may contain dangerous gases.
If the alarm will not clear, the pump or blower may be the cause. Have a licensed electrician or septic pro check the pump or blower. This is the end of the DIY road on this guide.
Washington's health department says service or repair of pumps and other electrical equipment must be done by a licensed professional. Your county health department sets local requirements.
What can you do yourself, and what needs a professional?
You can look at the breaker panel, limit water use, and, if yours is the homeowner-maintained type, clean the effluent filter. Everything electrical, and anything that needs tank access, is for a licensed professional.
Looking at the breaker panel for a tripped alarm or pump breaker
Washington's health department lists a tripped breaker as an owner check before calling for service. Look and note only. Turn off the power and unplug all cords before handling the pump or floats.
Resetting a tripped breaker
No primary source says a homeowner should reset it, so have a licensed electrician or septic pro do it.
What the pro does: Resets the breaker and checks the alarm and pump circuits.
Limiting water use while the alarm is on
Avoiding baths, showers and clothes washing is the step Washington's health department gives to buy time. It does not touch the system.
Cleaning a homeowner-maintained effluent filter
Only if yours is the homeowner-maintained type; the other type is maintained by your pumper. Never go into the tank.
Checking or replacing a float switch
Never go into the tank. No dollar figure is stated: a fair range was not available on this guide's two-source pricing track, so ask for a written quote.
What the pro does: Handles the float with the power off and cords unplugged, without anyone entering the tank.
Replacing a failed pump or blower
Estimates from two guides that disagree, so both are given rather than averaged: HomeGuide puts replacement at $500 to $1,300, repair alone at $250 to $400 (Dec 2025). Angi states repair at $250 to $400, replacement at $1,000 or more (Mar 2026).
What the pro does: Diagnoses the failure and replaces the pump or blower.
$500-$1,300verified Aug 2026
If it's still sounding, what to tell the dispatcher
Tell the pro what you already checked:
- Whether a breaker had tripped
- That you limited water use
- Which type of effluent filter you have
Ask for a written description of the work done.
Rules, and who is allowed to do the work
The alarm-circuit and lock-on requirements here are Texas rules, from 30 TAC Chapter 285 Source 1: TCEQ 30 TAC Chapter 285. Other states set their own rules, and a separate alarm circuit is not unique to Texas: Washington's health department says the same Source 4: Washington State Department of Health, DOH 337-087.
Washington's health department says service or repair of pumps and other electrical equipment must be done by a licensed professional Source 4: Washington State Department of Health, DOH 337-087, and UMN calls a trained, licensed and bonded professional the safest way to have repairs performed Source 2: UMN Septic Care and Maintenance. Who may legally work on your system, and what needs a permit, varies by state and local jurisdiction. Your county health department has the final word on permits and what is allowed on your property.
For routine care beyond this alarm, the septic owner's manual covers monitoring as ordinary upkeep rather than crisis response.
Common questions
How do I reset a septic tank alarm?
Most alarms have a manual silence switch, required by Texas code on every high-water alarm. Silence it only after you know why it fired. Resetting an undiagnosed alarm just hides the light, not the cause.
Who do I call when a septic alarm goes off?
Before calling for service, check for a tripped breaker. If that is not it, or the pump will not run, call a licensed septic professional. Alarms on pumps and filters must be attended to immediately.
What should I do when a septic alarm goes off?
Limit water use: avoid baths, showers and clothes washing. Look at the breaker panel for a tripped breaker; Texas code puts an electrical alarm on a circuit separate from the pump's. Resetting a breaker and anything else electrical is for a licensed electrician or septic pro.
Do all septic tanks have alarms?
No. A gravity system with no pump has no code-required high-water alarm, though it may carry a separate alarm on its effluent filter for a clogged screen. Only pump-equipped systems, including aerobic units, carry the high-water alarm this guide covers.
What causes an alarm on an aerobic septic system?
An aerobic unit is a pump-equipped system and must carry a high-water alarm under Texas code. Have a licensed electrician or septic pro check an aerobic unit's alarm.
Why is my septic tank alarm going off after heavy rain?
The guidance does not change with the weather. A faulty pump, float or circuit and excessive water use are all possible causes of a high-water alarm, so limit water use and attend to it right away.
Sources
- 30 TAC Chapter 285, On-Site Sewage Facilities (rule text): the alarm-circuit-separate-from-pump-circuit requirement, manual silence switch, and dual-pump alarm lock-on behavior. Texas Commission on Environmental Qualityaccessed Jul 2026
- Septic Care and Maintenance: the effluent filter and its alarm, the two filter types (homeowner-maintained and pumper-maintained), alarms attended to immediately, and never going into the tank. University of Minnesota Onsite Sewage Treatment Programaccessed Jul 2026
- Tribal SepticSmart Homeowner's Guide: the high-water alarm named as a pump-tank failure sign, for systems with pumps. US Environmental Protection Agency, SepticSmart programaccessed Jul 2026
- Understanding and Caring for Your Pressure Distribution System, 'What If the Alarm Comes On?': the alarm on a circuit separate from the pump, what to check before calling for service, never entering the pump chamber, and who services pumps and electrical equipment (DOH 337-087, Jan 2025). Washington State Department of Healthaccessed Sep 2026