Hello Victron community, just wanna share an experience that can be solved with Victron feature when charging your Lead-Acid battery bank produce Hydrogen. So, to begin, when I start my solar project I make the decision to have my battery in a isolated box with 2 outside vent in my cabin closet. Find it more convenient for maintenance & less exposure to cold temperature we encounter in my area. What happen is as far I try to airtight my cover box with rubber gasket, they still have Hydrogen leak in charging process that result to make my carbon monoxyde detector false reading & crazy beeping alert. The two outside air vent wasn't enough for gas evacuation. So after consultation with a good friend, we decide to use the MPPT open relay option to wire a computer fan in my upper box air vent. Bingo !!, I program the relay with the high voltage option, so everytime I'm charging, the Fan turn on escaping hydrogen out & giving a little chill to battery on warmer day in the same time. If this experience share can help someone here, Will be happy to hear it,, & thanks again Victron to offer so much possibility in your system that sometime result in safety & security purpose !!