Power Issues, and Carbon Monoxide Detectors

It is midnight, and we were prepping to go to bed tonight when an unusual beeping occurred.  We tracked it to our carbon monoxide detector in the bedroom.  It caused a bit of worry, but as we studied the device, we noticed that it was flashing red/green, and noticed that this indicates low voltage.

We also noticed upon reflection that the lights were quite dim, and the fridge indicator light was off.

The TV worked, so we were powering just fine off of the breaker of our friends' house, but we nonetheless, traced back to ensure all the cords to the garage were solidly connected, and the breaker was not tripped.  

The lights that were dim run off the batteries when boondocking, but we never quite grasped the difference between running off "shore power" versus the battery.  We noticed that the ceiling of the basement has a large inverter in it, so we deducted that the lights run off the batteries, but that the inverter is keeping them charged off the power line.

Tomorrow we will read the trouble shooting manuals on the system and seek confirmation, but we figure that after all the chills and winter entertainment, our 2 12 volt batteries are probably due for a replace.

As an extremely critical aside, a lot of places sell carbon monoxide sniffers that combine with smoke detectors, and in our case (an many others that I have noticed) the rig came with a wired in separate carbon monoxide detector and battery operated smoke detector.  Smoke detectors are best at ceiling level, but:

It is critical for you to note that a carbon monoxide detector MUST be placed at ground level as carbon monoxide is a heavy gas, and if you have a high wall or ceiling mounted one, by the time it detects the problem, YOU ARE dead or lethally poisoned.  

That being said, guess where they mounted ours.... high on the wall. (Which is why its beeping was so concerning...)  We have a second one that we bought and plugged in to a low to the ground outlet near our propane stove (one of the most likely sources should we have a problem)  The trouble with carbon monoxide is that it is scentless, and colourless.  

Anyway, we will likely have to replace the batteries, but they sure earned their keep this past winter!  We don't fault them for weakening now.  Definitely a tomorrow issue... which actually means later today I suppose.....

So good night folks, be safe, and now I must bid you 

Adieu.