Pat60 Report post Posted June 11, 2009 We have a 2-year-old Tiffin Phaeton motorhome. We have it serviced regularly. We keep it plugged into 50-amp service at home. We use it periodically. In March my husband opened the battery compartment and discovered a bulging battery and corrosion all on the bottom of the batteries. We took it in for service. All four batteries had to be replaced and the floor of the compartment was cleaned and painted before new batteries were put back. One month later, when preparing for our next trip, my husband opened the battery compartment and, lo and behold, corrosion was starting all over again on one of the new batteries. We were told several reasons for this and then finally service told us that it is our fault that this is happening. We are supposed to check the batteries every three weeks for the water level because we keep it plugged in all the time. For two years we did not have this problem and all of a sudden we have a battery problem and one month in between the replacement of the batteries. My husband always checks each compartment before each trip so we know that between January '09 and March '09 there was no corrosion. Can anyone give us some advice on this subject? We were told that we are probably going to have to replace the batteries every two years ... this is almost a $1,000 expense. Thanks Share this post Link to post Share on other sites
roadyachtcaptain@gmail.com Report post Posted June 11, 2009 You MUST check(or have checked) the voltage regulator for the battery charger. In the mean time, you can use a "sacrifice" post, best is some pennies, placed close to the battery posts; they will attract the free negative electrons in the acid cloud that is forming over your overcharging batteries, which are 'cooking' and leaving an oxide on everything the cloud touches. You will see corrosion forming on all the metal surfaces in proximity; Vaseline will protect them short term, but not after the corrosion has started. They will require cleaning and sealing,like the tray. Share this post Link to post Share on other sites
garykd Report post Posted June 11, 2009 Hi Pat60, Roadyacht gave a good suggestion. Make sure your charger is working correctly. Correctly depends on what kind of charger you have. Some a dumb and some are smart. The bottom line is that it should be reading around 13.5 VDC, when plugged into shore power. That being said, I have a recommendation for you. If/when you decide to replace the batteries, ask about AGM technology batteries. They are sealed. Never add water. Eliminates the corrosion in the battery compartment. The are expensive. For me, I got tired of checking the water. It is a pain in the you know where. So I bit the bullet and got AGM batteries. After 2 years, I made the correct decision. I crossed off my long list of owner maintenance items the checking of battery water. The batteries are as rugged as a tank. They hold their charge and last a long time. I recommend you consider this. Share this post Link to post Share on other sites
Pat60 Report post Posted June 14, 2009 Thank you very much for your replies...I appreciate the information. I must say that we have already replaced all the batteries to the tune of almost $1,000.00. No one offered to us waterless batteries and you can be sure when the time comes to do this again we will definitely check out the waterless batteries. Meanwhile we will also consider the pennies. Thank you once again. Share this post Link to post Share on other sites
wolfe10 Report post Posted June 15, 2009 Proper battery charging is important to battery life irrespective of what type of battery you have (wet-cell, AGM, gel). Proper FLOAT VOLTAGE (voltage AFTER batteries fully charged-- like more than 24 hours after plugging in) should be 13.0-13.5 VDC. In the summer, 13.0-13.2 VDC is ideal. Higher voltage WILL overcharge batteries, cause them to use water, etc. As suggested, not all devices used to charge batteries are equal. There are basically two levels of "quality" of chargers: "Stupid" converters-- those that charge at the same voltage whether the batteries are fully discharged or fully charged. "Smart" converters, "Smart" chargers or "Smart" inverter/chargers. Substantially better because they charge discharged batteries at a higher voltage (BULK MODE), then taper off in ABSORPTION MODE and after fully charging, maintain the batteries in FLOAT MODE. Please pull out the owners manual for your converter, charger or inverter/charger. If a "Smart" one, read the section on programming it. Make sure it is set on SUMMER/high temperatures. Unless it has a temperature probe found on real high-end units, YOU have to tell the charger whether the batteries are at freezing or 100 degrees F. And if set for winter temperatures, it will be overcharging the batteries when it is hot outside. If you have a "Stupid" converter or after programming your "Smart" charger, use a digital voltmeter (available at Radio Shack, Sears, etc starting under $25) to check voltage at the battery at least 24 hours after plugging it in (to insure you are measuring FLOAT voltage). Again 13.0 to 13.2 VDC is ideal in hot weather. Brett Wolfe Share this post Link to post Share on other sites