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Question About Sump Pump Battery Backup Float Location

By May 27, 2019 2 Comments

I have two Zoeller M53 AC pumps setup in a primary and backup configuration. I added the Zoeller Aquanot 508 battery backup pump to the main pump.


Do I want to position the backup float so that the backup AC pump will activate first in the event of the main pump failure? My understanding is the Aquanot DC pump only runs on battery, so in the event of a main pump failure I’d want the backup AC pump taking over and the DC pump should only activate in the event both AC pumps fail or we lose power.



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  • BeerNutsAndBolts says:

    Yes. I have a very similar set up with two Zoeller M98s, one as a primary and the secondary a few inches higher as a secondary (Backup AC) pump. The Zoeller Aquanot is positioned about a foot or so from the secondary AC pump. My pit is pretty deep at 48″ so you might have to size it for your pit.

    Good luck with the installation. I love the my Aquanot.

  • ThisIsAbuse says:

    There are three models of Aquanot’s 1) Active 2) FIT and 3) Base model. Only the Active can continue to run the pump on AC after draining the battery. The others will simply quit once battery is dead. However… if your cycling less than 10% (say 30 second pump, 5 mins off) the other models will be recharging the battery during those 5 mins of rest (no pumping) and its anyone’s guess if that “topping off the battery” will mean days and days of continued operation. I do wish Zoeller had made all their Aquanauts with large controllers/chargers to run the pump and charge the battery under AC.

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