Originally Posted by cudabuck
Thanks for the info, I am going to get that tool for sure. The unit has a WFCO Ultra III distribution center, WF-8900 series. Tracking the heated tank switch and circuit now. Also wanting to see if my Norcold fridge has the same condensation heater that the dometics do. Funny thing, I don't see a fuse for the tank heaters in the distribution center. Something has to be figured out, we can't even sleep all night without the beepers going off cause of low batts!
Well...you have a converter...not an inverter so no issues with drain there. That really will not be kind to your AGM batts over time... so if it tests bad ...you might want to consider replacing it with an AGM compatible model.
Can't speak to your norcold but you can probably access support materials on their site which will tell you about the design...or you can call their number.
Don't know your unit so can't help with where to look...but the problem has to be a big drain somewhere, or failed/undercharged batteries.
Remember...you don't know that your batteries are charged if you're plugged in. Plug in overnight to fully charge. Measure at the battery terminal while plugged in that you are getting at LEAST 13.2V....Then unplug AND
REMOVE the negative wire from the batts for 24 hours...THEN check battery voltage at the terminals with a multimeter before putting the wire back on. You should read 12.6 or 12.7 volts at that time. Less than 12.4 indicates significant loss of capacity. 12.2 or less means you've got battery replacement problems.
Once you know the batteries and charger are both good...via multimeter...not coach voltmeter readouts.... then you can proceed to find out your parasitic amp loads and big load drains with a clamp meter as discussed earlier.
If you get a clamp meter...be sure to get one that does AMPS in both AC & DC...some AC/DC clamp meters only do AC amps. One like this is what you need...