crscott46 Report post Posted December 14, 2018 I have 2002 Newmar Motorhome Class A and need some help on identifying a problem I am having. I purchased all new batteries last year for the motorhome and made the house batteries 12 volt. The motorhome has been in the garage since March this year. I have gone out twice the last 6 weeks to start it and each time the batteries are dead, I notice there is corrosion in the battery tray and all terminals are clean on the 4 batteries. Any advice of what is causing dead batteries as well as the corrosing in battery tray Share this post Link to post Share on other sites
manholt Report post Posted December 14, 2018 If you have any elect in garage, plug into it or put a separate trickle charger on your batteries. You got "phantom draw"! If you are plugged in to 30A or 50A, your overcharging and cooking batteries. You need to keep acid batteries full of distilled water. Share this post Link to post Share on other sites
ispjs Report post Posted December 14, 2018 X2 what Carl said. My Newmar is a DP and my engine batteries are very well vented plus they are sealed units, so never any corrosion there. My house bank are wet batteries and that compartment is not very well vented so I do see corrosion in there. I check the distilled water level every month but I still have to use a battery cleaner and wash everything out in there once and awhile. I suspect if it was vented better I wouldn't see as much. Share this post Link to post Share on other sites
dickandlois Report post Posted December 14, 2018 2 hours ago, crscott46 said: I have 2002 Newmar Motorhome Class A and need some help on identifying a problem I am having. I purchased all new batteries last year for the motorhome and made the house batteries 12 volt. The motorhome has been in the garage since March this year. I have gone out twice the last 6 weeks to start it and each time the batteries are dead, I notice there is corrosion in the battery tray and all terminals are clean on the 4 batteries. Any advice of what is causing dead batteries as well as the corrosing in battery tray Welcome to the FMCA Forum ! There are required electrical maintenance items. Carl did mention keeping them charged some how and a close eye on the water levels in the batteries. Using the charger / inverter built into the coach or a supplemental 10 amp. trickle charger. There are phantom loads as mentioned by Carl and they are always present. 12 volt coach wiring is drawing a level of current to power all the coach systems that require 12 volts. Refrigerator control module, furnace control system, water heater, water pump, 12 volt lighting, entry steps, power roof vents, the off air signal amplifier, smoke detector and CO-2 detector in some cases. One should turn off the 120 volt inverter. It will draw current from the coach battery bank, even when not needed ! Also, There are all ways loads on 12 volt wiring for the chassis batteries. Just parking and forgetting a RV no mater what class or size is a No / No. Rich. Share this post Link to post Share on other sites
hermanmullins Report post Posted December 14, 2018 To expound on what Carl, Joe and Rich said, There are alway Battery Gremlins that try their darndest to suck down your batteries. As said if you have electricity where you store your coach, leave it plugged in. This will allow your inverter to maintain your house batteries. But you will need a small charger to maintain your chassis batteries. I have one that is plugged into my Block Heater outlet. It is only hot when your are connected to shore power or when running your generator. Mine is mounted in my battery compartment. It chargers my house batteries then maintains they 24/7 when it is in the barn. Hope this helps. Herman Share this post Link to post Share on other sites
