Zoeller 508-0005 Aquanot 508 DC Battery Back-Up Sump Pump: Peace of Mind

There’s a saying in the sump pump world that there are two kinds of people: those who have backup sump pumps and those who haven’t lost power in a flash flood. In a nutshell, this means you need a backup sump pump no matter how good your AC main sump pump is, because if you lose power, your AC sump pump’s not going to do anything for you. And naturally, that power loss is going to occur when your main pump was working like crazy to keep up with a thunderstorm or flash flood. The math is simple: spending a few hundred dollars now can keep you from spending thousands more when cleaning your basement, buying new furniture, and replacing big screen TVs, stereos, video games, musical instruments, and other precious possessions after a flooded basement. So what’s worth buying?

When it comes to DC backup sump pumps, the best we’ve yet come across in terms of technological sophistication is the Wayne WSM3300. It’s a backup sump pump capable of running monthly self tests and calling you and several other numbers if your power runs out or if it runs into maintenance issues. Frankly, we love it. But if you don’t need or want the smart functionality, and simply want reliability, you might want to check out the Zoeller 508-0005 Aquanot 508 Battery Back-Up System. It’s one of the best DC backup pumps on the market, and works exceptionally well with a number of quality Zoeller AC sump pumps like the M267 (the best AC pump we’ve ever reviewed), the M98, the M63, the M57, and the M53. We’ll take a closer look at it below, but if you’re simply interested in knowing if it’s a good deal before buying it, know that we fully recommend it, and you can buy it here.

Key Features of the Zoeller 508-0005 Backup Sump Pump (60 Second Summary)

The Zoeller 508-0005 is  a pre-assembled battery backup submersible sump pump. The backup pump is a 12-volt DC-powered motor. It has a maximum water flow rate of 2,340 gallons per hour and comes with a variable warranty of 12 months from installation, 18 months from the manufacture date, or 36 months if purchased with a Zoeller Aquanot AGM battery and used as a backup pump. It is 10.5 inches tall, 8.5 inches wide, and 8.5 inches long and weighs 16.3 pounds on our scale. Zoeller specifically notes that this is not a bilge pump.

The Zoeller 508-0005 requires a 12-volte battery to function; this battery is not included. You will need to purchase a 27, 29, or 31-size deep cycle battery containing at least 175 minutes of reserve capacity with maximum dimensions of 13″ in length, 7.5″ in width, and 9.5″ in height to fit inside the supplied battery case. With additional hookup wire, you can add additional batteries. Examples of compatible batteries include the MK-E27-SLD-G we reviewed, as well as the Zoeller Aquanot AGM.

The Zoeller 508-0005 includes a control box that provides information through an LCD screen of battery voltage, including LED light indicators to alert you to battery charging states, AC power levels, and the activation of the float due to high water. You can also silence the high water alarm for 24 hours via the control box. Although the backup pump can pump a maximum of 2,340 gallons per hour at zero feet, the flow rate drops to 1,800 GPH at 10 feet, 1,200 GPH at 15 feet, 360 GPH at 20 feet, and shut-off occurs at 22 feet. The working temperature spans 40-120 degrees Fahrenheit. According to the manual, you’ll need a sump pit at least 18″ in diameter and at least 24″ deep, although you can probably squeeze it into slightly narrower pits.

How Does the Zoeller 508-0005 Compare to the Wayne WSM3300 Backup Sump Pump?

The main differences between the Zoeller 508-0005 and a smart pump like the Wayne WSM3300 lie in the sophistication of the latter’s self-monitoring and autodial features. While you can connect the Zoeller to a home security alarm or auto dialers, allowing you to receive texts, emails, or other notifications of alarm activation (e.g., the AC power alarm, the low battery alarm, or the high water alarm), it will not take these actions simply when connected to a phone line, the way the WSM3300 will. In that sense, it isn’t independently smart. What it does provide you with is a stellar level of reliability. We’ve seen 508 backup units in use for a decade after installation while continuing to work without a hitch. It is important to note, however, that the WSM3300 is also a significantly faster backup pump than the 508-0005. As we’ve noted in a different review, if absolute speed of water removal is a priority under a DC backup system, you’ll want the WSM3300.

Besides that, we found the Zoeller 508-0005 to be compatible with a wide range of primary sump pumps. In essence, the backup pump doesn’t need to know the primary pump exists; it simply benefits from the existence of the primary pump by not needing to run whenever there’s water in the sump pit. The float switch for the main pump is installed lower than that for the backup pump so the backup pump only activates when the main pump is having trouble keeping up with water flow (or of course, when a power outage occurs ans the main pump stops entirely).

Our Short and Long Term Experiences Installing and Using the Zoeller 508-0005 Backup Sump Pump 

Overall installation experiences were painless, even if you aren’t a sump pump installer. Remember to install a battery in the battery case and plug the whole unit in so the battery is kept on a full charge. If you want to take advantage of auto-dial features, you’ll also need to connect it to your dedicated alarm system.

In terms of long-term feedback, we’ve typically only heard good things about the Zoeller 508-0005, whether when installed independently or when installed as part of a combination sump pump package (e.g., the Zoeller 508-0007, or the Zoeller 508-0006). You can expect 10 years or more of reliable service from it if you’re lucky, and we’ve heard from a number of homeowners and plumbers with longer successful installations.

Troubleshooting and Installation Tips to Get Your Zoeller 508-0005 Working Sooner

When your installation is complete, check your indicator lights to make sure everything is in good shape. When AC power is connected, your AC light should be green; it will blink red when you lose power. Similarly, your battery charging indicator will be green with a fully charged battery, yellow with a charging battery, and red with a low battery. The red light will blink slowly for a voltage below 10.8 volts and quickly for a battery with fewer than 8.4 volts. Any low battery should trigger a low battery alarm.

A yellow light will blink when your float activates due to high water, and the light will remain solid after 3 seconds of activation. Your high water alarm should also activate along with your yellow light; remember that pressing the alarm reset will reset all alarms. If you press and hold it for 3 seconds, you will silence all alarms for 24 hours; this is handy when you know you’ve got a high water situation but have confidence that your pump or pumps will handle it.

Zoeller 508-0005 Backup Sump Pump’s Pros, Cons, and Value Comparison

Overall, we’re happy to recommend the Zoeller 508-0005 as a backup DC sump pump. It’s not a smart backup sump pump in the sense of the Wayne WSM3300, but it’s a reliable little machine that works well with a range of AC sump pumps. We’d recommend choosing the Wayne if you want the communicative and self-testing abilities it features (or if you need the high pumping rates it provides) and choosing the Zoeller if those aren’t priorities. Either sump pump will keep your basement dry.

You can buy the Zoeller 508-0005 here on Amazon. You can buy the Wayne WSM3300 here. You can buy the Zoeller 508-0007 here. You can buy the Zoeller 508-0006 here. You can buy the Zoeller 507-0008 hereYou can buy the Wayne WSSM40V here. You can buy the Zoeller AGM battery here. You can buy the MK E27-SLD-G battery here.

If you find our work at PumpThatSump helpful, you can put our relentless reviewing of every pump and fixture on the market to the test by shopping via our links above for whatever you need to make your house a home. Despite being self-employed, we promise not to spend it all on health insurance.