Guide · Home care
Septic Pump Alarms
What a septic pump alarm means, the few simple things residents should do when the light comes on, and what to leave to the owner and the pros.
Where to start
- Alarm sounding right now?
Stay calm, cut water use right away and call the owner's emergency line. See when the alarm goes off.
- Power out?
The alarm may not sound while the power is out, so keep water use light. See during a power outage.
- Just moved in?
Find the alarm panel and ask whether someone can show you the silence button. Start with the checklist.
The short version
Some homes cannot send septic water to the drainfield by gravity alone, so they use a small pump to move it. That pump has a helper: an alarm that sounds and flashes if the water gets too high.
The first time you hear it, it can be startling. Please know that the alarm is doing its job. It is giving everyone time to act before there is a problem in the home. You will not be bothering anyone by calling.
What the pump and alarm do
In these systems, water flows from the septic tank into a second tank called a pump chamber. Floats inside the chamber rise and fall with the water. One float turns the pump on, another turns it off, and a higher float sets off the alarm if the water keeps rising.
The alarm usually has a red light and a loud horn, and the panel is often on an outside wall, in a garage or in a utility room.
When the alarm goes off
- Stay calm. The alarm is an early warning, not a disaster.
- Silence the horn only if you have been shown how. Many panels have an outside silence button that quiets the horn but leaves the light on. If you are not sure, leave it alone.
- Cut water use right away. Hold off on laundry, the dishwasher, showers and baths, and flush as little as you can.
- Call the owner's emergency line. Share what you see and hear, and the time it started.
The chamber usually has some extra room above the alarm level, but how much varies from home to home, so please do not count on it. Using water normally while the alarm is on can cause sewage to back up into the home.
Who does what
Every home and lease is a little different, so these are examples. When you are not sure, ask first.
Residents can often
- Knowing where the alarm panel is
- Cutting water use as soon as the alarm sounds
- Calling the owner's emergency line and sharing what you see and hear
- Silencing the horn, only if you have been shown how
Leave to the owner or a pro
- Opening the pump chamber lid
- Opening the control panel or resetting breakers inside it
- Switching the pump to manual or testing it
- Touching, pulling or cleaning the floats
What residents should never do
Pump chambers and control panels are septic equipment, so they are always a job for the owner or a licensed septic pro. Residents should never:
- Open the pump chamber lid or lean over an open chamber.
- Open the control panel or reset breakers inside it.
- Switch the pump to manual or try to test it.
- Touch, pull or clean the floats.
Septic tanks and chambers may hold dangerous gases, and the panel carries electricity, so only trained septic pros should open or work on them. Your job is to watch, cut water use and report, and that is a very important job.
What the owner or pro will do
The owner or septic pro will check the power and breakers, test the pump, and look for floats that are stuck, tangled or blocked by debris. They may also check the pump itself and the line to the drainfield. Once the problem is fixed, the water drops and the light goes out.
During a power outage
The pump needs electricity, so it cannot run when the power is out. The alarm may not sound while the power is out, so keep water use light even when it is quiet. Use water as lightly as you can until the power comes back, and let the owner know if the alarm sounds once power returns.
Your septic pump alarm checklist
From the guide’s own checklist. Tick each one as you go. These are examples; your home may need others.
All done. Thanks so much for taking care of your home!
Signs to watch for and report
Here are some common examples. This is not a complete list.
- The alarm light or horn, even if it stops on its own.
- A pump that seems to run all the time.
- Wet ground or sewage smells near the pump chamber.
- Slow drains, gurgling or water backing up into the lowest drain.
An everyday example
Late one evening, a resident heard a loud buzz from the garage and saw a red light on the septic panel. The owner had shown the family the silence button at move in, so they quieted the horn, turned off the dishwasher halfway through its cycle, and texted the owner a short video. A septic pro came the next morning and found a float stuck in place with debris. Once it was cleaned, the pump ran, the water dropped and the light went out. The family's quick, calm steps kept the problem in the tank and out of the home.
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Go deeper with The Perfect Country Rental
Septic pumps and alarms are one of several systems that make a country home different from a home in town. The Perfect Country Rental walks through wells, septic systems, fuel deliveries, power outages, winter roads and the distance to help, with worksheets for who does what.
Keep this guide handy
Save this page, come back to your checklist any time, and share it with anyone in your home who could use it.
See all guidesTake it with you
- Bunklow Home Guide 107: Wastewater Lift Pump Chamber Float Switches and High-Level AlarmsA printable Bunklow guide to wastewater lift pump chamber float switches and high-level alarms: plain steps, how often to check, and when to call a pro.See it in the shop
This guide shares general educational information to help you, and is not legal advice or a substitute for a licensed professional. Bunklow does not inspect, repair or service septic systems. Septic rules differ from state to state and county to county, so please check your state and local law, follow the maker's instructions, and get local help from a licensed septic professional for any work on the pump, panel or tank.