InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
This article describes alarm systems used on septic pumps, grinder pumps, and septic tank pumping stations and pumping systems. This article series explains the differences between Sump Pumps, Sewage Ejector Pumps, Septic Grinder Pumps, Sewage Pumping Stations, & Septic Pump Alarms.
Our video at right demonstrates the operation of a septic tank pump system alarm. Septic alarms indicate when the septic tank pump is not operating. Repair is needed promptly.
Advice is given for septic tank effluent or sewage pump selection and use.
Septic pumps used for pumping air in aeration systems and septic pumps used to move effluent in a drip dispersion system are discussed under the appropriate septic system type which are outlined at SEPTIC SYSTEM DESIGN ALTERNATIVES.
Citation of this article by reference to this website and brief quotation for the sole purpose of review are permitted. Use of this information at other websites, in books or pamphlets for sale is reserved
to the author.
Use & Operation of Single septic pump alarm system details
Any sewage pump setup should include an alarm that tells you when a pump has stopped working.
It is important to be able to distinguish between blocked building drains, failing septic systems, and lost function of a septic pump. Otherwise you will soon be unable to run plumbing fixtures and you may not know why.
In a single-pump septic system (shown in the photograph at left and at page top) if you hear the septic alarm buzzer or bell it means that you have very little septic capacity before repairs are
made, since there is no working pump.
Use & Operation of Duplex septic pump alarm system details
In a duplex septic tank pump system, (shown in photo at left) sounding of the septic alarm indicates that
you're running on the backup pump.
You need to repair the failed septic pump but you can continue to use the building's plumbing fixtures as the backup pump should be working.
There are two different philosophies for designing duplex backup systems - alternating septic pump cycles and reserve septic pump installations. We discuss simplex and duplex septic pump installations and the different methods of designing a duplex septic pump system in more detail at SEWAGE EJECTOR / GRINDER PUMPS
Frequently Asked Questions (FAQs) about septic system or grinder pump alarms
Question: why is the septic alarm going off in our new home?
What happens with a new home less then 6 months old and the alarm keeps going off? - Carol 8/18/11
Reply:
Carol, septic pump alarm systems operate on a sensor or float control that monitors wastewater level in the septic tank or pumping chamber. The idea is that if the level rises above some point, the alarm warns the homeowners that the single pump has failed to start, or if it's a duplex pump system (two pumps) that the first pump didn't work and the second pump has started (the backup pump is doing all the work).
You need to know from the installer what design you have;
Perhaps there is a pump to repair or replace (duplex pump, running off backup) or there is a pump alarm float switch that is not set to the proper level.
Question: Our septic alarm gose off if the system loses power.
Checked all the floats, everything working fine. Pump ok, high level alarm ok, Q: the alarm goes off if the power goes off to the system. It has never done this before. If I turn off the breaker, and back on, the alarm sounds until I silence and reset. - Mike 10/13/11
Reply:
Mike in the past when we heard about alarm sounding problems the problem was usually traced to a float that had slipped out of position. As you've checked the floats and wastewater levels I'm afraid it sounds as if there may be as shorted wire. The float is basically a switch that closes to sound the alarm. So I'd check the float switch or the actual wiring. If you use an ohmmeter and see zero resistance across the wires that are supposed to trigger the alarm, the wires are probably shorted or the switch is stuck.
Also check for a battery-backup alarm system that is intended to warn of loss of power - basically we can't keep using a septic grinder pump very long if there is no electrical power. The usage time buffer depends on the size of the holding tank.
Reader follow-up:
Thanks. I will disc. the float wires and troubleshoot from there.
Reply:
Sounds right, Mike. In fact if you can disconnect the wires at both ends that's another way to check for a short between them enroute.
Question: why does a grinder pump alarm go off on a seldom used system?
What are the most common causes a pump tank alarm would go off? My grinder pump is only 4 yrs old and we are still building, so it does not get that much use,. C.S. 8/5/12
Reply:
A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem with a sewage pump such as a defective check valve or a running toilet that keeps filling the reservoir tank.
That said, the grinder pump alarm sounds when the level in the reservoir reaches a level that in turn signifies that the primary pump is not working, or in a single-pump system, that the pump is working and the level of wastewater has reached the level at which the alarm will sound.
So check your plumbing system for:
a running toilet draining into the toilet or even a running shower or faucet
ground water or some other water source (A/C condensate?) draining into the grinder pump reservoir
bad check valve that lets other household wastewater drain back into the grinder pump reservoir
also
check that the float switch is properly installed and is at the right level
...
Ask a Question or Search InspectApedia
Questions & answers or comments about warning alarms on septic tanks and septic pump systems
Ask a Question or Enter Search Terms in the InspectApedia search box just below.
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.
...
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.
Advanced Onsite Wastewater Systems Technologies, Anish R. Jantrania, Mark A. Gross. Anish Jantrania, Ph.D., P.E., M.B.A., is a Consulting Engineer, in Mechanicsville VA, 804-550-0389 (2006). Outstanding technical reference especially on alternative septic system design alternatives. Written for designers and engineers, this book is not at all easy going for homeowners but is a text I recommend for professionals--DF.
Builder's Guide to Wells and Septic Systems, Woodson, R. Dodge: $ 24.95; MCGRAW HILL B; TP;
Quoting from Amazon's description: For the homebuilder, one mistake in estimating or installing wells and septic systems can cost thousands of dollars. This comprehensive guide filled with case studies can prevent that. Master plumber R. Dodge Woodson packs this reader-friendly guide with guidance and information, including details on new techniques and materials that can economize and expedite jobs and advice on how to avoid mistakes in both estimating and construction. Chapters cover virtually every aspect of wells and septic systems, including on-site evaluations; site limitations; bidding; soil studies, septic designs, and code-related issues; drilled and dug wells, gravel and pipe, chamber-type, and gravity septic systems; pump stations; common problems with well installation; and remedies for poor septic situations. Woodson also discusses ways to increase profits by avoiding cost overruns.
Country Plumbing: Living with a Septic System, Hartigan, Gerry: $ 9.95; ALAN C HOOD & TP;
Quoting an Amazon reviewer's comment, with which we agree--DF:This book is informative as far as it goes and might be most useful for someone with an older system. But it was written in the early 1980s. A lot has changed since then. In particular, the book doesn't cover any of the newer systems that are used more and more nowadays in some parts of the country -- sand mounds, aeration systems, lagoons, etc.
The Home Reference Book - the Encyclopedia of Homes
