Battery Life

[HoosierDaddy]

My recently acquired '93 Newell has Interstate 8D batterys dated 2004. I'm not sure how long the coach has been sitting prior to my buying it but it sat outside in some 0 degree conditions this last winter. All batterys are dead but the main engine batterys have been taking a charge from my battery charger for almost 24 hrs. They started out taking 30 amp (max output for the charger) and are now down to around 15 amp. Is that a good sign? How long should they charge before I remove the charger and expect them to function properly?
Thanks

Dean :?:

[Richard and Rhonda]

I don't know the direct answer, but here is a round about way of checking. Take them off charge, and wait for at least two hours before you measure the voltage. If it's 12 or better, at least you are getting signs of life. Now put them back on charge for 4 hours or so, take them off for two, and measure the voltage again. If it is better than before, great!, even better signs of life. If it is flat, then, you have all the charge in them that they will take.

You could read the individual cells with a hydrometer, but the voltage way is an overall check of the battery.

Good luck !!!!!! Batteries do not like to be left in a discharged state, and many never forgive you for it. Also, in your climate, a discharged battery will FREEZE, something you do not want to happen

[fulltiming]

The fact that the charger when to max charge indicates that the batteries were discharged, but then you knew that already. Since the charge is backing down, the batteries are recharging. I would tend to let then charge until the charger is down to 3-5 amps, then disconnect the terminals from both the charger, from each other and from the coach. Wait for about 30 minutes, then take a voltage reading on each battery. Then, similar to Richard's suggestion, wait for several hours and recheck the voltage. You may find that a good long slow recharge will bring all of the batteries back.

If these are not 'sealed' batteries such as AGM's, make sure that distilled water is added to each cell before recharging.