Wayne WSSM40V Pre-Assembled Combination Sump Pump Review: The Best Battery Backup System Under $600

When we install sump pumps for homeowners, one of the most frequent questions we ask is if they’d like to consider a combination AC/DC system. There are always homeowners simply interested in the cheapest reliable sump pump solution (we recommend the CDU800 in such cases); however, after discussing the degree to which they value their basement possessions, most people realize that a combination AC/DC sump pump system is a highly effective (and highly affordable) way of buying peace of mind. In the event of a power failure, a typical AC sump pump simply stops working, leaving your basement with the same degree of protection as that you’d have if you’d never installed a sump pump to begin with (and of course, these power outages tend to occur in the middle of flash floods when you need your sump pump the most). A combination AC / DC system, however, simply switches from AC power to a separate DC-powered sump pump that gives you a fighting chance to keep your basement dry for another 24-96 hours, depending on flood rates, the depth of water you’re pumping, and your battery configuration. In our books, this is a much better solution. So what’s the best AC/DC system out there?

We once reviewed the Wayne WSS30V, which combines the CDU800 (a good AC sump pump) with the ESP25 (a good DC backup sump pump). We also reviewed the WSM3300, a high-end DC backup sump pump with the ability to self-test both pump and battery functionality as well as the ability to call you during power outages when the backup pump springs into action. We thought it would be great if the power of the CDU800 could be paired to the smart functionality of the WSM3300. Fortunately, Wayne was already ahead of us and combined both in the Wayne WSSM40V Combination Primary and Backup Sump Pump System. If you’re looking for the best combination AC/DC sump pump system under $600, stop looking; it’s here. Our full review is below, but if you’re simply wondering whether or not to buy it, then yes, we recommend it, and you can buy it here.

Key Features of the Wayne WSSM40V Sump Pump (60 Second Summary)

The Wayne WSSM40V is a pre-assembled primary and battery backup combination submersible sump pump system. The main sump pump is AC-powered and is the CDU800; the backup is DC-powered and is the WSM330V. The main pump features a 1/2 horsepower motor while the backup features a 12 volt motor. The primary pump features a 4,200 gallon per hour maximum water flow rate (3,300 GPH in the backup), and a 5 year limited warranty . It’s 15.5″ tall, just under 18″ wide, and 23″ deep with a maximum pumping height of 20 feet and a switch-on/switch-off height of 4″ and 9″ respectively. The aforementioned pump switch is vertical.

The WSSM40V draws 15 amps and is equipped with a battery backup, although the battery isn’t included; you’ll need a 12 volt deep cycle battery with either 40 amp hours or 75 amp hours. It weighs 34 pounds, and has an 8 foot-long power cord. Although the main discharge flow can reach 4,200 gallons per hour at 0 feet, it drops to 3,150 gallons per hour at 10 feet, 2,100 gallons per hour at 15 feet, and 500 gallons per hour at 20 feet. The backup discharge flow is 3,300 GPH at 0 feet, 2,300 GPH at 10 feet, 1,500 GPH at 15 feet, and 400 gallons per hour at 20 feet.

The working temperature spans 40-140 degrees Fahrenheit, it’s self-priming and housed in cast iron and stainless steel, and the sump pump outlet diameter is 1-1/2″ FPT. It’s designed to be used with sump pits (sump basins) at least 15 inches in diameter.

It features a programmable computer system to monitor battery status and a trickle charger designed to maintain battery charge at optimal levels. The system performs a self-test of the sump pump every 14 days and can be programmed to call 5 different phone numbers in a variety of situations, including pump activation, high water levels, low battery charge levels, and pump malfunctions.

How Does the Wayne WSSM40V Compare to the WSS30V Sump Pump?

The primary differences between the WSSM40V and the WSS30V are in the configuration of the backup pump; because the WSSM40V features the WSM3000 instead of the ESP25, you get the benefit of a smart backup sump pump with self-monitoring and external phone-home abilities. It can monitor its battery status, keep an optimal charge more effectively, test the pump’s functionality, and call 5 numbers due to a range of identified problems (e.g., power outages and high water levels). To put it simply, the addition of the WSM3000 makes the WSSM40V a far more sophisticated and functional combination sump pump system than any other on the market.

It’s worth noting that the maximum working height of the WSSM40V is slightly smaller at 20 feet than the 22 feet of the WSS30V; the temperature range is also shifted upward, even though it ends up being wider than that of the WSS30V. With the WSSM40V, functionality is guaranteed between 40F and 140F, while the range is 33F-120F in the WSS30V.

Our Short and Long Term Experiences Installing and Using the Wayne WSSM40V Sump Pump

We found installation straightforward (keeping in mind that this is our profession). We’d estimate it might take the average homeowner with some plumbing experience 1-3 hours to make the connections. Because it’s pre-assembled, most of the work is already done. There are two check valves present beneath both pumps, so it’s basically a question of connecting a battery, plugging in the two units, and attaching a main discharge pipe. Keep in mind that the manual, as is typically the case with Wayne’s sump pumps, wasn’t written specifically for the WSSM40V, which means that you’ll want to use it more as a guide than as gospel.

The noise levels are low, low, low. The main pump, the CDU800, is one of the quietest models out there, while the WSM3300 is only going to be audible when it runs self-tests or when it’s actually working during power outages, and it’s next to silent in both situations.

Troubleshooting and Installation Tips to Get Your Wayne WSSM40V Working Sooner

The main things to remember during installation are that the WSSM40V, being a battery-powered backup pump, will need a 12 volt deep cycle battery to work; if you don’t attach one, your pump won’t work. Because it’s a smart pump, it’ll call you to let you know, which is great, but it’s best to take care of this right away. You’ll want to choose either a 40 or 75 amp battery; if you try to use a larger battery, you might not get it to fit in the battery box. You need a 27-frame sized battery. Per Wayne, you can obtain up to 92 hours of operation; we were able to get around 90 hours (equivalent to roughly 4 days and 3 nights when running every 5 minutes), which we found acceptable.

Once you’ve installed the WSSM40V, you’ll want to test it by pumping water from a garden hose into your sump pump basin after turning off the main pump and the backup pump’s trickle charger; this simulates a power loss. Once this occurs, the backup pump should engage as soon as the float switch is triggered. The backup pump will test itself in a similar way every few weeks, but you’re better off conducting the first test while you’re there to observe the results.

Finally, to take full advantage of the phone-home feature (which is worth the price of the WSSM40V by itself), you’ll need a phone cord that connects to the pump from a phone jack in your house (e.g., one on your ground floor or in the living room). You’ll also need to ensure that your phone service will continue to run during a power outage. This occurs naturally in most communities due to phone lines being on separate systems than electricity lines, but it’s best to make sure before a power outage occurs so your pump will be able to call for help in a dire situation. A lot of phone systems these days (e.g., Verizon FIOS) include backup batteries in their systems; these are good, but make sure you test them now and then too.

Wayne WSSM40V Sump Pump’s Pros, Cons, and Value Comparison

In conclusion, it’s hard to say enough good things about the WSSM40V. It combines the reliability of the CDU800 with the enhanced functionality of the WSM3300 to create what’s without a doubt the best combination AC/DC sump pump systems you can buy today. Simply being able to have your sump pump call several different numbers (e.g., your number, your neighbor’s, your plumber’s, your best friend’s, etc) to let them know about a range of problems (such as high water levels or low batteries or simply the activation of the backup pump) makes this the system to buy for anyone seriously invested in having a dry basement 24/7. This is the next best solution to hiring someone to watch your basement around the clock.

If you’re simply looking for a great AC sump pump, we’d recommend the Wayne CDU980E as our top choice. If you already have an AC sump pump you love but want the best battery backup on the market, you can buy the WSM3300 as a standalone unit. And if you don’t want smart technology but simply want a solid AC/DC combination system, we recommend the WSS30V.

You can buy the Wayne WSSM40V here on Amazon. You can buy the Wayne WSM3300 here on Amazon. You can buy the Wayne WSS30V combination sump pump here. You can buy the Wayne CDU980E sump pump here. You can buy a 75Ah backup pump battery here. You can buy a battery terminal set here.

If you find our work at PumpThatSump helpful, you can support our relentless testing of every sump pump on the market by shopping via our Amazon link for whatever you need to make your house a home. Despite being self-employed, we promise not to spend it all on health insurance.

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