Thor Forums

[javelin]

Well typically the house batteries provide 12vdc for your coach DC loads but they also power the generator starter motor (as you found out) and hydraulic leveling jack pump motor if equipped. Batteries fail for many reasons and one of them is plate sulphation from inadequate or not getting regular appropriate charging voltages.



The best procedure is to buy a multi-meter (voltmeter) and check your battery string voltages (coach and chassis) to make sure they are charging under normal conditions (on shore; on gen and when engine is running). Some coaches don’t necessarily charge both strings at the same time so you will have to determine if that applies to you. If the battery strings are receiving at least 13vdc or more they are charging at least.



When parked in your driveway plug into shore power....even if you only have a standard 15 amp house connection (use the appropriate 30 amp adapter on your shore cord). Note the use/store must be on to charge house batteries (and chassis batteries in many coaches) when on shore power. If your house batteries are dead/discharged the use/store latching relay will not work to allow charging from shore (unless it failed in the on position), so you will either have to charge them with a car battery charger first (some new car chargers wont work with dead batteries either); or you may have to boost them from a known good 12 vdc battery (tow car?) just enough to get the latch relay to turn on so shore power can start charging. Check it is with your new voltmeter.



Many folks on this forum use auxiliary battery disconnect switches on the battery terminals to completely disconnect batteries when the coach is stored (log on and do a search). Note though wet cell batteries require regular charging at high enough voltages to remove sulphates from the battery plates, so leaving them disconnected for very long storage times can result in shorter battery life.