The Best Battery Backup Sump Pumps for the Home

If your power goes out during a storm, a battery backup sump pump can help you stay worry-free and your basement water-free.

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The Best Battery Backup Sump Pump Options

Photo: amazon.com

Basements are subject to flooding because they’re below grade. If water trickles in, it has no place to go. Many basements have a sump pump installed in a pit in the basement floor to help in these situations. When water begins to fill the pump basin, the pump kicks on and pumps the water out of the sump pit. As long as the pump is receiving electricity, it’s a reliable system. Unfortunately, storms that bring torrential rains and flash flooding also sometimes bring high winds and lightning that can down a power line or knock out a transformer, leaving your home without electricity for hours or even days. Without the pump to remove water, the basement may flood.

For those times when the power is out, it’s a good idea to have a backup plan for removing water from the basement. Enter the battery backup sump pump. When the electricity goes out, the backup pump switches on and takes over, pumping out water until the power returns. The best battery backup sump pump for your home depends on how often your current sump pump cycles to remove water and how long a power outage typically lasts in your area. The following eight battery backup sump pumps will step up when the power goes out.

  1. BEST OVERALL: WAYNE BGSP50 Guardian Basement Protection System
  2. RUNNER-UP: THE BASEMENT WATCHDOG Model BW4000 Sump Pump
  3. BEST BANG FOR THE BUCK: THE BASEMENT WATCHDOG Model BWE Backup Sump Pump
  4. BEST EASY INSTALL: Zoeller Aquanot 508 Sump Pump System w/ Battery
  5. BEST LOW MAINTENANCE: Superior Pump 92900 12V Battery Back Up Sump Pump
  6. BEST COMBINATION: Zoeller ProPack98 Spin Primary & Backup Sump Pump
  7. BEST SMART: THE BASEMENT WATCHDOG Model BWSP Sump Pump with WiFi
  8. BEST GPH: THE BASEMENT WATCHDOG Big Dog CONNECT 3500 GPH Sump Pump
The Best Sump Pump Options

Photo: depositphotos.com

What to Consider When Choosing the Best Battery Backup Sump Pump

Dependability and durability are among the top considerations when choosing a battery backup sump pump. When shopping for a backup sump pump, how quickly it can remove water and how long it can run before the battery runs down also are important features.

Material

Battery backup sump pumps often feature housings made from heavy-duty thermoplastic, stainless steel, or other waterproof materials designed to resist corrosion. The housing also should be sealed to prevent moisture from getting inside the pump’s components.

Pedestal vs. Submersible

Like primary sump pumps, a battery backup sump pump can be one of two types:

  • Submersible: A submersible model sits in the sump pit, which is in the basement floor. When water enters the pit, the water level begins to rise, and when the water reaches a certain level, the pump kicks on to pump the water to the surface.
  • Pedestal: The pumping motor of a pedestal sump pump sits atop a column, and the base of the column sits in the sump pit. The column is approximately 2 to 3 feet tall, and the pump motor sits above the floor. Since the pump sits above the water, it must be moisture-resistant but not fully waterproof like a submersible pump.

Battery and Runtime

Battery backup sump pumps run on 12-volt, acid-free batteries. Some manufacturers recommend a battery that’s marine rated, which means it will withstand moisture better than a standard 12-volt battery. A 12-volt battery’s power can range from 40 amp-hours to 80 amp-hours or more, with 75 amp-hours the most common. The higher the amp-hours, the more powerful the battery and the longer the backup pump will run. How quickly a battery runs down depends on how much water is entering the sump pit and how often the pump must cycle to pump it out.

For example, if a backup sump pump cycles once every 4 minutes and pumps out 1.5 gallons with each cycle, a 40-amp-hour battery might last 32 hours, while a 120-amp-hour battery might last closer to 96 hours. However, if the pump cycles every minute, the 40-amp-hour battery’s runtime will fall to around 8 hours, and the 120-amp-hour battery would last closer to 24 hours.

Another factor comes into play: After four or five years, a 12-volt battery will start to lose some of its ability to hold a charge. This means that an older battery will have less runtime. Choosing a powerful battery—and replacing that battery every four or five years—is the best bet for keeping the basement free from unwanted water.

Gallons per Minute

Also known as its capacity, a backup sump pump’s gallon-per-hour (GPH) rate is an estimate of the maximum amount of gallons it can pump out in an hour when the battery is fully charged. This number usually appears on the pump’s label or in its product description, and it’s directly related to the power (measured in horsepower) of the pump. Most backup sump pumps will remove an average of 1,800 to 2,000 GPH at a 10-foot lift, which means they can pump that much water to a height of 10 feet, which is the typical height necessary to remove water from below a basement to the ground level.

Ease of Installation

Installing a battery backup sump pump isn’t a difficult project. It requires basic plumbing techniques, but many communities require a licensed plumber to complete the installation. Check with your local building authority to find out the rules in your community.

The simplest type of backup pump to install is a combination unit, consisting of both a primary pump and a backup pump nested together. Because the two pumps come connected, there’s no need to splice the drainpipe to add a second pump.

Our Top Picks

A battery backup sump pump should be durable and powerful enough to protect the basement from flooding if the power goes out. The following models are some of the best options for keeping your basement dry in any kind of weather.

Best Overall

Photo: amazon.com

Those in the market for a new primary pump in addition to a backup pump may want to look no further than the Wayne Basement Guardian premium protection system. It features a primary pump that plugs into a household outlet and comes with a nested, ½-horsepower backup sump pump that accepts a 12-volt battery (sold separately). Both pumps are made from cast iron and aluminum, and the unit is submersible. The primary pump can pump up to 3,840 GPH of water at a 10-foot lift, and the backup pump can pump up to 2,040 GPH to the same lift. This combo unit connects to home Wi-Fi systems, and it syncs with a smartphone to provide alerts when the power is out and the backup sump pump is active.

Runner-Up

The Best Battery Backup Sump Pump Option: THE BASEMENT WATCHDOG Model BW4000 Sump Pump
Photo: amazon.com

The BASEMENT WATCHDOG Special CONNECT sump pump with battery backup is a combination unit that includes both a primary sump pump and a battery backup pump. This nested, submersible pump is constructed with cast iron and cast aluminum for durability. It’s designed to run on AC unless the power goes out, and then the battery backup pump kicks in. The pump runs on a 12-volt battery, which is not included.

The primary pump is rated to pump 3200 GPH at a 10-foot lift, and the backup pump is rated to pump 1730 GPH of water to that same height. For the longest runtime, choose a battery with 75-amp-hours or higher. This unit is not Wi-Fi capable, but in the event of a power loss, it will emit an audible alarm.

Best Bang for the Buck

The Best Battery Backup Sump Pump Option: THE BASEMENT WATCHDOG Model BWE Backup Sump Pump
Photo: amazon.com

You can protect your basement from flooding without having to spend a lot of money. The BASEMENT WATCHDOG battery backup sump pump is rated to pump 1,000 GPH at a 10-foot lift. Since it’s a secondary pump only, a primary pump also must be installed with it in the sump basin. The submersible pump housing is made from heavy-duty thermoplastic to make it waterproof and corrosion-resistant. This affordable backup pump runs on a 12-volt battery (not included) with a minimum 75-amp-hour runtime.

Best Easy Install

The Best Battery Backup Sump Pump Option: Zoeller Aquanot 508 Sump Pump System w Battery
Photo: supplyhouse.com

With the Zoeller Aquanot sump pump with battery backup, the backup pump doesn’t have to connect to the primary pump because it’s a combination unit. It comes fully assembled, ready for a plumber to install in a basement sump pit. This submersible unit is made of cast iron and thermoplastic components that resist rust and corrosion. The primary pump is rated at 2.040 GPH with a 10-foot lift, and the ⅓-horsepower backup pump is rated for 1,800 GPH of water with the same lift. The unit also comes with a lockable battery box, which requires a 12-volt battery that’s not included. When the power goes out, it lets you know with a light indicator and an audible warning.

Best Low Maintenance

The Best Battery Backup Sump Pump Option: Superior Pump 92900 12V Battery Back Up Sump Pump
Photo: amazon.com

Made from corrosion-resistant, thermoplastic construction, the Superior Pump battery backup sump pump should provide years of reliable protection from flooding when the power goes out. It comes with an easy-to-remove and clean intake screen filter that keeps debris from entering the pump’s motor. It also comes with a thermoplastic battery box to protect the 12-volt battery (not included) from moisture and corrosion. The Superior Pump is a backup-only pump, and it must be installed alongside a primary electric sump pump. The pump is rated to remove up to 1080 GPH of water to a 10-foot lift; for the best results, use a battery with 75 amp-hours or higher.

Best Combination

The Best Battery Backup Sump Option: Pump Zoeller ProPack98 Spin Primary & Backup Sump Pump
Photo: sumppumpsdirect.com

For high efficiency and flood protection in a combination unit, look no further than the Zoeller ProPack combination primary and backup sump pump system. This nested unit features a primary pump rated to pump 3660 GPH of water at a 10-foot lift and a backup pump rated to pump 1,800 GPH to the same lift. The combination unit features an engineered thermoplastic exterior, and the housing is filled with oil and sealed hermetically to protect the pumps. The battery charger has an LED screen that displays the voltage left in the battery and other essential system information. When the power goes off, the Zoeller combination pump system emits an audible alert. The unit works on both AC for the primary pump and a 12-volt battery (not included) for the backup pump.

Best Smart

The Best Battery Backup Sump Pump Option: THE BASEMENT WATCHDOG Model BWSP Sump Pump with WiFi
Photo: amazon.com

Receive notifications when the power goes out with the BASEMENT WATCHDOG battery backup sump pump with Wi-Fi. This submersible, backup-only pump is designed to sync with your home’s Wi-Fi system and send notifications directly to your smartphone via a downloadable app. You also can monitor the pit’s fluid level and the remaining battery charge from your phone. This sump pump is designed for use with an existing primary sump pump, and it runs on a 12-volt battery (not included). When the power goes out, it springs into action, pumping up to 1,730 GPH water to a 10-foot lift. In addition to sending notifications to a smartphone, the backup pump emits an audible alarm when the power goes out or when maintenance is needed.

Best GPH

The Best Battery Backup Sump Pump Option: THE BASEMENT WATCHDOG Big Dog CONNECT 3500 GPH Sump Pump
Photo: homedepot.com

For peace of mind in those homes where the sump pump regularly cycles—even when it’s not storming—consider the BASEMENT WATCHDOG Big Dog CONNECT battery backup sump pump. This submersible backup pump is rated to pump 2,250 GPH of water at a 10-foot lift, making it the backup pump with the highest GPH rating on this list. It features sealed thermoplastic housing for long-lasting water protection, and it also comes with Wi-Fi capability, so you can download the app on your smartphone and receive notifications. This is a backup-only sump pump and should be installed next to a primary sump pump. It runs on a 12-volt battery (not included), and the manufacturer suggests using a marine-rated battery for the best results. Users can connect an additional battery for double the runtime.

The Advantages of Owning a Battery Backup Sump Pump

Peace of mind is the most significant advantage of owning a battery backup sump pump. Without a backup pump to remove the water that drains into the sump pump basin, flooding can follow a power outage.

  • A battery backup pump offers peace of mind in case the power goes out.
  • A connected backup sump pump can send notifications to your smartphone to let you know the pump’s status.
  • A combination battery backup unit includes both a primary pump and a backup pump to make installation easier.

FAQ About Your New Battery Backup Sump Pump

If this is the first time you’ve shopped for a backup sump pump, you probably have some questions. Keep reading to find the answers to some of the most popular questions about backup sump pumps.

Q. Can you add a battery backup to an existing sump pump?

Yes, the backup pump installs in the same sump basin, and when the power goes out, the backup pump begins to pump out water.

Q. How long do battery backups last for sump pumps?

Battery backups last until the battery runs down, which can be anywhere from an estimated six hours to 90 hours or longer. The amount of time depends on the battery’s size and how quickly water is flowing into the sump pit.

Q. Do I need a plumber to set up a battery backup sump pump?

You probably need a plumber for installation. Similar to installing a primary sump pump, setting up a battery backup sump pump requires connecting a new pipe to the existing system. The process involves installing a check valve and ensuring the fittings are watertight. In many communities, building codes require a plumber to make those connections.