Bests & Worsts Reviews from Amazon

I am an electrical engineer. I too used to own a BWD system until I discovered its many flaws when it failed during a heavy rainstorm. First flaw - the BWD pump's capacity is nowhere near sufficient to take over for a primary pump during a power outage. if you get "heavy flow" in your sump, the BWD will not be able to handle it, good battery or not. you will flood eventually. 2nd flaw - the BWD charger overcharges the battery. Mine held a constant 14.7V at all times. this is too high for a 6 cell lead acid battery. it boils the electrolyte and eventually kills the battery. 3rd flaw - the "battery sensor" (really just a capacitive water sensor) only measures electrolyte level in one cell (out of the 6). so, as the charger boils off electrolyte, you have a 5/6 chance that the battery will fail before the sensor tells you it needs water. this is what happened to me. 4th flaw - the system relies on the consumer to properly assemble a 150ah lead acid battery (e.g. add the electrolyte, etc). Glentronics does this because they do not have the supply chain or manufacturing capabilities to supply fresh batteries to the market place like the big car battery manufacturers do (e.g. Johnson Controls). "joe consumer" who doesn't know anything about batteries is not the right person to be adding electrolyte to a dry 6 cell. battery failure is the result. But don't take my word for it -- next time there's a big rainstorm go to Home Depot and watch the BWD batteries fly off the shelf. this is an epidemic. so what's a better solution??? read on... forget the weak DC powered pumps. I have yet to find one that has the power to pump >2000 gph. instead get 2 high quality AC powered "primary" pumps and power them with a DC/AC power inverter/charger with auto transfer switch ($250) run by one or more standard deep cycle marine batteries or golf cart batteries ($100 each). the number of batteries depends on how long you want backup power. I actually prefer 2 6V golf cart batteries connected in series as it is less sensitive to variations in battery condition. 12V marine batteries should be wired in parallel. in my case I actually have 2 inverters each powered by 2 golf cart batteries -- e.g. each pump has its own dedicated power supply. complete redundancy = peace of mind for only $800 complete for both pumps, 4 batteries, and 2 dedicated power inverters. but make no mistake -- the glentronics BWD stuff is junk. plain and simple junk. Edit (12/2014). After 4 years of use I am changing my opinion on the use of Golf Cart batteries (or any "true" deep cycle battery that is *not* maintenance free and/or has Calcium/Antimony plates). I am not changing my opinion on basement watchdog products (still junk) or their assemble-yourself batteries. The problem with "true" deep cycle batteries is that they do in fact out-gas excessively over time while being float charged, while the maintenance free marine deep cycle batteries do not noticeably out-gas. This is important for a couple reasons - with marine batteries you don't have to keep refilling the electrolyte and you don't have the excessive hydrogen out-gassing into your home & the air you breathe. Now for some reason my Golf cart batteries did not out-gas much at all during their first 2 years, but then suddenly they started needing to be refilled every 6-8 weeks, and I could smell the fumes in the basement. not a good thing. Meanwhile my setup using marine deep cycle batteries has never needed water in over 4 years. For an in-home application that will not need repetitive deep-discharge cycling, marine batteries are definitely the way to go. Walmart is a great place to buy them (Everstart are made by Johson Contorls). So to recap - still hate the basement watchdog junk. Still love the power inveter/deep cycle battery solution. Now recommend regular maintenance free marine deep cycle batteries and *not* Golf Cart batteries.