When it comes to home design and engineering, we’re believers in a few basic principles. First of all, if you have a basement, you should have a sump pump. Second, if you have a sump pump, it should have a battery backup. If not, you’re asking for a flooded basement (and all the problems that come with one) the first time you lose power during a rainstorm. This will, of course, happen while you’re out of town on business or vacation. And who wants to come home to that?

As a result, it’s no surprise that we think combination sump pumps are a good idea, and we frequently recommend them when installing pumps. We recently discussed the importance of including a battery backup in our review of the Wayne WSS30V combination sump, which we think is easily the best combination sump pump system under $400 you can buy today. However, if you’re on a slightly smaller budget, you might be interested in the Wayne WSS20V pre-assembled combination sump pump system. We took a look ait to figure out how it compared to the WSS30V. If you’re in a hurry, we recommend the WSS30V for most homeowners and the WSS20V only if you have minimal sump pump needs and simply want a bit of basement flood insurance.

Key Features of the Wayne WSS20V Sump Pump (60 Second Summary)

The Wayne WSS20V is a pre-assembled primary and battery backup combination submersible sump pump system. The main sump pump is AC-powered and is the CDU790; the backup is DC-powered and is the ESP15. The main pump features a 1/3 horsepower motor while the backup features a 12 volt motor. The primary pump features a 3,800 gallon per hour maximum water flow rate (1,750 GPH in the backup), and a 3 year limited warranty . It’s 11.5″ tall, 17″ wide, and just over 22″ 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 WSS30V draws 9.5 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 27 pounds, and has a 8 foot-long power cord. Although the main discharge flow can reach 3,800 gallons per hour at 0 feet, it drops to 2,700 gallons per hour at 10 feet, 1,700 gallons per hour at 15 feet, and 100 gallons per hour at 20 feet. The backup discharge flow is 1,750 GPH at 0 feet, 720 GPH at 10 feet, 300 GPH at 15 feet, and is inoperational at 20 feet.

The working temperature spans 40-120 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.

How Does the Wayne WSS20V Compare to the WSS30V Sump Pump?

As you can see, the main differences between the WSS20V and the WSS30V are that the WSS30V is a much more powerful and efficient machine. Specifically, the main sump pump is significantly stronger in the WSS30V at 1/2 horsepower over the 1/3rd horsepower motor in the WSS20V, and the flow rates are higher in both the main and backup pumps at every level we tested. Perhaps most significantly, the warranty is chopped nearly in half in the WSS20V at 3 years compared to a full 5 years in the WSS30V.

Our Short and Long Term Experiences Installing and Using the Wayne WSS20V Sump Pump

The WSS20V was as easy to install as the WSS30V, which was easier than nearly any other sump pump we’ve installed (keeping in mind, as always, that we do this hundreds of times a year). Wayne’s approach to combination pumps is to do most of the pre-installation work for you; you won’t need to buy or install additional check vales, for example, and you can almost literally drop it into the sump basin and plug it in. You’ll also need to attach a battery and a main discharge pipe. Keep in mind that the included manual, while written in English and reasonably accurate, is also exceptionally general, which means much of the information in it won’t specifically apply to the WSS20V.

Noise levels in the WSS20V were equivalent to those in the WSS30V, or in other words, nearly non-existent. We couldn’t hear it working from more than a few feet away unless we strained our ears, and reports from homes where we’ve installed it suggest it’ll effectively be inaudible for all but the most sensitive ears.

We’d rate the 1/3rd horsepower motor in the primary sump pump as strong enough to keep small basements (or those with low water tables and low levels of flooding) dry; however, we’d really prefer to see 1/2 horsepower main motors (such as that found in the WSS30V) these days given how much larger basements have become in the last few decades with ever-widening houses. That said, the design is a tested and proven one, and we would be surprised if most homeowners didn’t get at least a full decade of service out of the main or backup pump systems in this unit. Keep in mind that the battery will naturally need to be replaced before then due to the inevitable degrade in power (much as in a car battery, which, by the way, can also be used to power the backup pump).

Troubleshooting and Installation Tips to Get Your Wayne WSS20V Working Sooner

Perhaps the most significant tip we provide families when installing the WSS20V is that you’re going to need to connect a 12 volt deep cycle battery to the unit. If you don’t, you’ll simply be working with the CDU790, and the CDU790, being an AC pump, will be completely useless if the power ever goes out. We suggest (as does Wayne) that you buy either a 40 or 75 amp battery; a larger battery might not fit in the battery box.

Another point to keep in mind is that the unit doesn’t come with battery terminals; if you’re interested in using either a car battery or a marine batter, you’ll want to buy a battery terminal set.

Wayne WSS20V Sump Pump’s Pros, Cons, and Value Comparison

In conclusion, we’re hard pressed to recommend the WSS20V when the WSS30V is only a few dollars more. If the price difference were in the hundreds, we could make a strong argument for the WSS20V. However, as Wayne has currently priced the two, there’s very little reason to choose the WSS20V over the WSS30V; the latter offers far more power, a far better warranty, and will fare far better at keeping your basement dry in the worst weather conditions. However, if you absolutely need to save those few dollars, the WSS20V is a more than acceptable combination sump pump system for the money; it only pales in comparison to its more equipped sibling.

You can buy the Wayne WSS30V combination sump pump here on Amazon. You can buy the Wayne WSS20V combination 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 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.

When we make house calls to replace sump pumps, one of the options we always recommend is that of a replacement sump pump with a battery backup system. It’s not strictly necessary for a home, but we’ve seen enough flooded basements with working sump pumps that stopped working during power outages to know what a difference it can make. A combination sump pump (a primary AC-powered unit a DC-powered backup unit) can save you tens of thousands of dollars in basement flood repair costs, particularly if you have a finished basement or valuables stored in an area dependent on your sump pump.

With that in mind, it’s no surprise that when clients ask us whether or not we think the extra $200-odd dollars for a backup system is worth it, our answer is unequivocally yes. As a result, today we’re going to take a look at one of our favorite combination sump pump systems, the Wayne WSS30V Pre-Assembled Combination Sump Pump System. It’s essentially the pump and battery backup version of the Wayne CDU800, and at under $400, it’s the single best sump pump system on the market at that price. Our full review is below, but if you’re wondering whether it’s worth it, yes it is, we recommend it, and you can buy it here.

Key Features of the Wayne WSS30V Sump Pump (60 Second Summary)

The Wayne WSS30V 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 ESP25. 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 just under 14″ tall, 14.4″ wide, and just under 14″ deep with a maximum pumping height of 22 feet and a switch-on/switch-off height of 4″ and 9″ respectively. The aforementioned pump switch is vertical.

The WSS30V draws 10 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 24 pounds, and has a 9 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 is inoperative at 20 feet.

The working temperature spans 33-120 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.

How Does the Wayne WSS30V Compare to the CDU800 Sump Pump?

As noted above, we reviewed the CDU800 recently, and the main difference between the WSS30V and the CDU800 is the fact that an additional 12 volt back-up pump (the ESP25) is attached to the CDU800 (with a battery you need to supply) that allows the combination sump pump system to run even if AC power is cut. You need a significantly larger sump pit diameter (15 inches vs 11 inches) to fit the sump pump. The warranty is increased from 3 years to 5 years, the power cord is lengthened from 8 feet to 9 feet, and the weight and dimensions of the combination sump pump also increase.

Our Short and Long Term Experiences Installing and Using the Wayne WSS30V Sump Pump

Overall, we had a seamless experience installing the WSS30V (keeping in mind, of course, that we do this for a living). Unlike Wayne’s typical AC pumps, the WSS30V is pre-assembled and preset to speed up the installation process; they describe it as drop-in, which is rather close to the truth. Check valves are included in the base of both pumps (the main AC and the backup DC unit), which means all you need to do is attach a battery, plug in the AC unit, and attach a main discharge pipe. The manual that comes with the unit isn’t actually written for the WSS30V, which means that a lot of what you read in it won’t apply to the WSS30V (for example, the fact that you won’t need to install the check valves and that you can simply plug and play the unit).

Once again, Wayne doesn’t disappoint with functionality or with noise management; despite having a pair of pumps connected to each other, the WSS30V is still one of the quietest sump pumps currently on the market. It makes sense when you consider that only one pump should ever be working at a time (the main pump under normal conditions and the DC pump during a loss of AC power); for most people, the sump pump will be effectively inaudible unless you’re right next to it, and even then, you’ll barely notice it’s on. The backup pump is just as quiet.

Overall, the 1/2 horsepower in the main unit is strong enough to keep most basements bone-dry and is sufficient for most tasks. We’ve seen this design going strong after 4 years, and we expect most buyers to get at least a decade out of this pump system without significant problems in the main or backup pumps (besides replacing the battery, which will need to be done every few years for optimal performance).

Troubleshooting and Installation Tips to Get Your Wayne WSS30V Working Sooner

Keep in mind that in order to have an effective backup system, you need to attach a 12 volt deep cycle battery to the sump pumps; otherwise, you’ll basically just have the CDU800, which, of course, only works as long as you have AC power. We recommend (and Wayne instructs) you stick with 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.

Remember that the battery pump still needs support when handling the unit; if you only pick up the unit by the AC pump’s handle, you could break the flexible pipe fitting that connects it to the DC pump, leaving you with a broken connection at best and a damaged pump and battery at worst that you’ll need to replace.

If you have no plumbing experience, you might need an hour or two to install the system; the primary issue most people seem to have is fitting the unit into sump pits with 90 degree elbows. Your particular installation setup will of course depend on how your sump basin and piping is setup. Keep in mind that you’ll need at least a sump basin at least 15 inches wide to get the combination pump in.

Something else to keep in mind is that no battery terminals are connected to the unit; if you’ve got a marine or car battery you’d like to use, you’ll need a battery terminal set.

Wayne WSS30V Sump Pump’s Pros, Cons, and Value Comparison

In conclusion, we’d be hard pressed to recommend another sump pump to any family without a battery backup. The peace of mind you can buy for only a couple hundred extra dollars is well worth the tens of thousands you can save the first time you lose power during a period of heavy rain. The WSS30V works well, is dead simple to install, comes with a nice long warranty, and is effective at keeping basements bone dry. We can’t think of a better sump pump system for under $400.

You can buy the Wayne WSS30V combination sump pump here on Amazon. 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 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.