Vantage premature console power loss Options

[chungp]

Dear Colleagues,

This Vantage Pro Plus console is kept in a clear plastic-roofed/mesh-sided greenhouse. Location humidity goes from 60's to 90's, total rainfall 89 mm (1st half March) and temperature from 16C - 25 C. The power goes prematurely (happened after 2 weeks with new Duracell replacements). On using the AC adapter with same batteries inside, display returns and remains even after AC is unplugged (however, low battery signal appears, remaining with rest of display for several hours).

Has anyone experienced this? Any suggestions?

Thanks