Hi,
The CO meter can draw 0.4 amps from the battery 24/7 until it is dead, it takes about 3 weeks for a larger set of golf cart batteries. Propane meter adds the amp draw of the propane solenoid, and this total is about 0.8 amps.
If plugged in, then the converter should be putting out upwards of 40 amps per hour to keep the battery full. I would start looking there. Chances are that the 2 week old batteries can be saved, but never will reach their full output. Perhaps you can get 90% of their rated capacity now.
A simple 120 - 150 watt solar panel can solve all these problems.
SunElec.com The costs are now down to the $1 per rated watt range.. For about the cost of the new batteries, you can protect them forever. Well maybe not forever, but my original set of T-105 golf cart batteries lasted 13 years, while it's replacement set lasted 6.5 years of full time usage. The solar panels that I installed in 1994 are still in use, and lighting up my friend's house with 12 VDC light panels. My pair of 120 watt panels are used to light up my home now. I don't know when the solar panels will wear out, but am hopeful they will last me another 50 years, when I will not care if they are working or not.
Overall, my refrigerator, CO and propane detectors use about 35 AH daily, enough to discharge my 4 golf cart batteries in about 7 days. This is made up by 1 of the 120 watt panels. The other panels are used to run things such as the TV and other loads.
Fred.