Today we’re going to review the MK Deep Cycle 12 Volt E27-SLD-G backup sump battery. However, before we do, it’s worth quickly reviewing why you’d want one to begin with. To put it mildly, no sump pump is foolproof, and AC sump pumps, no mater how good, have one crucial dependence: alternating current (i.e., electricity).
Even if you’ve got the best sump pump on the market, it’s not going to pump an ounce of water if you lose power in the middle of a rain storm. And in our experience, this is when you’re most likely to lose power (especially if you have a finished basement and are out of town; it’s practically guaranteed at that point). As a result, you need a backup sump pump, whether DC-based or water-based.
The best DC sump pump is the Wayne WSM3300, while a cheaper but good alternative is the Wayne ESP25. However, whatever DC system you invest in will need–you guessed it–a DC power source (i.e., a battery). Just as not all batteries are equal when it comes to powering things as large as cars or as small as TV remotes, you also don’t want to take a gamble with a cheap sump pump backup battery; you’re literally putting everything in your basement at stake.
Fortunately, there are a number of good models out there that won’t cost an arm and a leg. Let’s look at the MK Deep Cycle 12 Volt E27-SLD-G backup sump battery and see how it works in a variety of DC backup sump pumps. If you’re ready to buy and just want to know if you can rely on it, then yes you can, and you can buy it here.
Key Features of the MK E27-SLD-G Battery (60 Second Summary)
The MK E27-SLD-G is a deep cycle battery suited for backup sump pump and marine applications. It has a nominal voltage of 12V and C/5, C/20, and C/100 capacities (e.g., the 5 hour, 20 hour, and 100 hour rates) of 72Ah, 88Ah, and 99Ah respectively. It weighs 63 pounds and is 12.83 inches long, 6.56 inches wide, and 9.3 inches tall including the size B (T876) terminals. It is self-sealing, rated as non-spillable, includes a lead calcium plate alloy and a sulfuric acid thixotropic gel electrolyte. The charge voltage at 77 degrees Fahrenheit spans 13.8-14.6 volts while the float voltage spans 13.4-14.6 volts. It is designed to be maintenance free (e.g., it does not require refills or level checks).
MK E27-SLD-G Compatibility with Various DC Backup and Combination Sump Pumps
We found the E27-SLD-G compatible with a range of DC backup and combination sump pumps. More generally, you can expect it to work with any device that needs a 12 volt power supply. So far, we’ve been able to confirm compatibility and functionality with the Wayne WSM3300, Wayne ESP25, Wayne WSSM40V, Wayne ESP15, and Big Dog Basement Watchdog. We’ll continue to test it with a range of backup and combination sump pumps, but our notes from fellow plumbers and homeowners suggests it has a high range of compatibility with just about every current system on the market.
Our Short and Long Term Experiences Installing and Using the MK E27-SLD-G Battery
MK claims an average lifespan of 7-8 years with a general life expectancy of 5-10 years; in comparison, they state regular deep cycle batteries are designed to last for 3 years or less. We’d agree with both of their assessments; a cheap deep cycle battery will typically die and require replacement within 1-3 years. Buying such a battery is a poor investment of time and money. From comparing notes with fellow plumbers and homeowners, we’d rate the average lifespan of an E27-SLD-G as between 6 and 9 years, which fits nicely within their broader predictions.
MK E27-SLD-G Battery Pros, Cons, and Value Comparison
Overall, we’d rate the E27-SLD-G as a strong choice for DC backup and combination sump pump applications. It’s capable of delivering a good and consistent amount of power and we’re more than satisfied with its short and long term reliability. It’s not the cheapest deep cycle sump pump battery on the market, but we’ve been in business long enough to know that you’re not going to be patting yourself on the back for saving a hundred dollars when your sump pit is filling in the middle of a flash flood and your backup sump pump won’t start. Spend a bit more for quality gear that won’t let you down when you need it most. The E27-SLD-G is quality gear.
You can buy the MK E27-SLD-G battery here on Amazon. You can buy the Wayne WSM3300 DC smart sump pump here. You can buy the Wayne ESP25 DC sump pump here. You can buy the Wayne WSSM40V combination AC/DC sump pump system 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.