Used an Adventurer Opti in August 2011 for about 20 quarts, then stored unit with batteries out of unit in separate ziploc until Sept. 2012. Re-inserted batteries and attempted to use unit--unfortunately, not before hitting the trail. Unit would seem to turn on with one press, small sensor light and green indicator LED would begin flashing, but as soon as I put the unit in water, the indicator LED would turn solid red and the sensor light would shut off, with the UV light never having come on.
Back home, measured battery voltage, and both CR123's at about 2.89V.
How low can battery voltage go, and unit still work?
Shouldn't the batteries have maintained their voltage longer? (Steripen claims 50 liters). Tried cleaning contacts (which looked good), tried warming batteries (ambient temps 50 F+, not cold).