Why it matters
Basement Watchdog states the BW-27AGM gives up to 40 hours of protection on the Big Dog, 48 hours on the Special+ and Big Combo (BW4000, CITS-50), and 80 hours on the Emergency (BWE) and Combination systems, each at a 10% duty cycle.
It's maintenance free with no water to add. Older pre-2014 systems with a remote terminal can show false alarms with an AGM battery, so check compatibility first.
Who it's for, and who should skip it
Good fit if
- Basement Watchdog owners
- Owners who want no maintenance
Look elsewhere if
- Pre-2014 Watchdog systems without the right terminal
- Other brands
Pros and cons
Pros
- Maintenance free
- Stated runtimes per system
- Matches Watchdog chargers
Cons
- Older systems may false-alarm
- Heavy
- Price
Limitations to weigh
- Charge and check backup batteries on the backup maker's schedule; most last three to five years.
Specifications
Every figure below comes from the source shown in brackets. Where the maker doesn't state something, we say so instead of estimating.
| Dimensions (seller) | 8 x 12 x 12 inches | Retailer |
|---|---|---|
| Product weight | 22.6 kg | Retailer |
| Model number | BW-27AGM | Retailer |
| Warranty | Warranty | Retailer |
Alternatives worth comparing
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- Jackel SF1850S Slotted Basin Cover
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- PumpSpy CV-150 Silent Check Valve
- Zoeller 30-0040 Quiet Check Valve
All sump pump accessories, compared in one table · Every Basement Watchdog product we cover
Final verdict
The battery to pick for a current Basement Watchdog system.
Where to buy
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