Ed B. from Washington posed a question that might be on your mind, too—
“I’m wondering about replacing the factory converter/charger unit with a ‘smart charger’. Battery management seems to be my problem just now. When in storage, the batteries go down to zip or overcharge, both of which are hard on the batteries. We have no problems while underway.
I tried putting a small charger unit on the batteries while in storage, but the small constant draw seems to fool the charger in to delivering full charge all the time without activating a trickle delivery as it is designed to do. Is this why Airstream has not put ‘smart charging’ units in at the factory?”
The converter/charger that Airstream installs works very well for the vast majority of cases. It is perfectly adequate unless you (a) want integrated inverter capability; (b) switch to AGM or other type of batteries; (c) want a faster charge rate, or some bells & whistles; (d) add a lot more battery capacity.
Before you spend money on an upgrade, try a few other basic steps:
2. During long term storage, disconnect the battery cables and put the trickle charger on. Make sure what you have is really a smart trickle charger designed specifically for storage of batteries and not simply a battery charger with a “float mode”. If the latter, then all you’ve done is replace your Airstream’s charger with another one that is doing exactly the same thing.
3. As an option, if your Airstream is stored outside, consider a solar panel and solar charge controller. A 100 watt panel would be plenty to keep your battery happy under average conditions.
4. Make sure you are maintaining the water level in the batteries during storage. Consider switching to AGM batteries. These will not “boil off” (lose water) during charging cycles so you don’t have to check the water level during storage, and they last longer.
5. If you have the ability to measure current draw on the battery while the trailer is stored and the Battery Disconnect is switch to “STORE”, do so. Parasitic draw may account for up to half an amp, but if it’s higher than that you have a voltage leak or device that isn’t working properly, and that will kill the battery pretty quickly.