Power outages are the most common reason sump pump systems fail. A battery backup system protects against this hazard and ensures that your sump pump system will still protect your home in the event of a power outage. If you regularly experience even brief power outages due to strong storms, a battery backup will likely pay for itself by preventing expensive water removal, repairs, and other issues caused by flooding.
There are several ways to back up your sump pump system, and it’s important to choose the right option for your sump pump system.
What Are the Best Ways to Back up a Sump Pump?
Add a Secondary Pump
Some homeowners choose to install more than one sump pump in their basements so that if the main pump fails or there is an extreme flooding event, the secondary pump/s can take over or supplement the efforts of the primary pump. Secondary sump pumps also help if there is too much inflow of water that a single pump can’t keep up with or gets overwhelmed.
While there’s nothing wrong with installing a secondary electrical pump, most sump pump failures are actually electrical, not mechanical — and if there is a power outage, a second electrical pump isn’t going to be able to run either.
Add a Battery-Powered Pump
Another option is a secondary pump that runs off a 12-volt DC battery. There are many such pumps on the market, and this is a popular solution chosen by many homeowners.
These pumps are designed to work in conjunction with the primary pump, providing a backup in case the main pump experiences electrical or mechanical failure. Typically, these secondary pumps have much lower pumping capacity than the primary pump, so they work best for short periods — such as a brief power outage. For many homeowners, this is an appropriate level of protection. If you live in an area where extremely high water levels or lengthy power outages are common, however, a battery-powered pump might not be sufficient.
Add a Battery Bank to the Existing Pump
Rather than installing a secondary pump or adding a battery-powered pump, homeowners can add a battery backup to their existing electrical pump. These wall-mounted systems combine a DC to AC inverter and a battery bank to create an uninterruptible power supply.
The Pump Sentry is one such product. Installation involves hanging the Pump Sentry on the wall, plugging the pump into it, and then connecting the Pump Sentry to a 12-volt battery. Other brands’ products work in similar fashion.
This type of system doesn’t offer any backup in case of a mechanical pump failure, of course, but since most pump failures are due to loss of power, it allows the main pump to operate at full capacity, without interruption, in the more likely event of a power outage.
Install a Water-Powered Sump Pump
Unlike traditional battery backup sump pumps, a water-powered sump pump uses municipal water pressure to siphon water out of the sump basin and away from the house. These pumps are considered very reliable, in part because the lack of a battery means there is no risk of loss of power or capability over time. Because they connect to the municipal water line, however, they are not an option for homeowners on well water, and if the city’s water system fails or is shut down for any reason, the water-powered backup pump will no longer work. They are also controversial because they use a lot of municipal water to operate — about 1 gallon of city water for every 2 gallons they pump out — causing some cities to ban them; check with your local authorities before buying one of these.
Learn more about how these pumps work on the website for Water Commander, a brand of water-powered sump pumps.
The Best Battery-Powered Sump Pumps
When shopping for a battery-powered sump pump, consider not only cost but also power, battery life, ease of installation, type of pump, and material. This article by Your Guy offers a great breakdown on these factors.
Here are three battery-operated pumps that consistently receive high marks from reviewers. No matter which battery backup pump you choose to buy, keep in mind that if the battery doesn’t work, the pump won’t either — and batteries require regular attention. You’ll need to check the battery water level every few months, clean the battery terminals twice a year, and budget for a replacement battery about every five years.
Basement Watchdog Emergency Sump Pump
Along with other Basement Watchdog models, this pump gets high marks for its relatively low price, long running time (up to 6 hours on a fully charged battery), and capacity (able to handle most moderate flooding situations).
Pros:
Lower price than most competitors.
Lightweight and portable.
Uses any 12-volt battery.
Cons:
Doesn’t self-test its battery, so you’ll need to check it yourself.
Wayne BGSP50 Guardian Basement Protection System
Wayne products are regulars on these top-pump lists, but we’ve included this specific model here because it’s not just a backup — this is a primary pump AND a backup. If you’re looking to replace your primary pump, you might want to consider this two-in-one purchase.
Pros:
Connects to home wi-fi and syncs with smartphones to give you alerts when the power is out and the backup pump is running.
Made from curable cast iron/aluminum.
Cons:
Battery sold separately.
Zoeller Aquanot Spin 508 Sump Pump
This battery-operated backup pump comes with an integrated check valve, making it easy to install. It’s also made from durable aluminum, and offers nice features like an LCD screen, self-testing, and protection from battery over-charging.
Pros:
Long (36-month) warranty.
Fast, efficient charging.
Cons:
Higher price than competitors’ similar models.