charge / use cycle
- Some batteries requre a certain percentage of juice left in them to fully charge, and if you go above or below that level, it reduces the charge. So while you think "I just charged the batteries", what really happened is that they did not become fully charged due to a failure to use the proper charge / use cycle.
2. Insufficient voltage from engine alternator
to re-charge battery
- Some boats have added extra electric
kit over the years without adding the extra battery bank to run them, or the extra powerful engine alternator
to charge the bank. Remember that your alternator will only produce power at the rate of engine rpm's, so if you have a weaker alternator it may not be possible to charge your bank fully at simple idle speeds, so you may need to monitor
your charge rate based on your rpm's and adjust as needed.
- Could be some kind of corrosion
or poorly grounded line from the fridge to the power source.
Trace the route
from the fridge to the power, and if all's good, then you have a power storage
(batteries) or power generation (alternator / whatever) issue.
Check the levels with a multimeter and you should be able to find the issue.