The Monitor is a combination of a voltmeter that read the voltage when the engine is running.
The ideal voltage is 12.75 if is less than that, your battery need to be charge or you have excess electrolytic/water mixture.

If is higher that 12.75 on the Display you have to add electrolytic, follow the instructions on your manual.
The green LED light let you know than your system in working, in case that your red light goes on you need to add water to the water tank.
Hydrogennie Systems Inc. Florida USA
Technical Support Monday-Friday 9:00 AM to 5:00 PM
Phone Number 1-305-879-0679
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