Batteries Won't Keep A Charge

[karaokegal@cox.net]

I have a 2006 Holiday Rambler Imperial. Ever since the day I bought it new I can not keep my batteries hot. Many service centers have looked at my coach, but no one has solved the problem. I have changed out my batteries to AGM batteries thinking this might help but it did not. I have 4- 6 volts to the house and two 12 v to engine.

Okay, I store my RV at a facility where it is plugged into 50 amp power at all times. Within 8-10 days I have to go to the facility and start the engine. If I don't I will have totally dead batteries within the next couple of days. I have also replaced the house batteries .

My question is this, do you think i have a bad inverter? First of all tell me this, are my 4- 6 volt batteries suppose to be hooked up in series, or parallel?

Also, the 2- 12 volt engine batteries in series or parallel?

I thought that I remembered reading some place that these batteries communicate with each other to try to maintain the charges. How can I test to see if i have a bad inverter or see if it is a solenoid problem?

Does anyone know where the solenoid is located in this RV?

I am getting tired of starting the engine every week or so.

Also I read on this site that I am not suppose to just start the engine in place, but i have to.

Any suggestions..

[wolfe10]

Lots of questions-- let's start with how the batteries are wired.

The chassis batteries (two 12 VDC batteries) are wired in PARALLEL. That is positive of battery #1 to positive of battery #2 to house positive. Negative of battery #1 to negative of battery #2 to house negative/ground.

House batteries (4-6 VDC batteries): Each pair of 6 VDC batteries is wired in SERIES to make "a 12 VDC battery in two cases". So House positive is wired to positive of battery #1. Negative of battery #1 is wired to positive of battery #2 and negative of battery #2 is wired to house negative/ground. Since you have two PAIRS of these, each PAIR is wired in parallel.

There is no way we can tell you where your charging system is failing without more information. Make sure the inverter/charger's breakers (on the 120 VAC breaker panel) are on. Make sure the resettable breaker on the inverter/charger (some inverters have them external, some internal) is ON/RESET.

Next, before plugging into shore power, measure voltage at the house battery with a digital voltmeter. Plug in and verify that the voltage rises-- unless batteries are deeply discharged, voltage should rise to 13.2 14.5 VDC. If it does not, check voltage at the inverter/charger.

And some coaches have both battery banks wired so they are charged by the inverter/charger, others are wired so that only the house batteries are charged by the inverter/charger. If the latter, you will need a trick l start, Echo charger, etc to charge the chassis batteries.

And, indeed, it is bad for a diesel engine to be started UNLESS you can drive it enough highway miles to get the oil (not just coolant) up to operating temperature. Anything less just adds a lot of moisture to the crankcase.

Brett

[wvashaw]

I had the same problem with my 2006 H.R. Navigator. Turns out I had a bad wire connection from the alternator to a relay located in the black electrical box in the engine compartment. Took two years to find. Sorry I forgot the name for the relay but it controls the voltage from the alternator and inverter.

[wolfe10]

I had the same problem with my 2006 H.R. Navigator. Turns out I had a bad wire connection from the alternator to a relay located in the black electrical box in the engine compartment. Took two years to find. Sorry I forgot the name for the relay but it controls the voltage from the alternator and inverter.

Wonder if you are referring to the BATTERY ISOLATOR RELAY (one of the two types of battery isolators used on RV's) . Allows alternator to charge both battery banks, but separates the battery banks when the engine is off so that the house batteries do not discharge the chassis batteries. If so, a failed relay or wire from alternator to relay would keep the alternator from charging either battery bank.

I don't think this is the OP's problem, as the alternator is his only means of charging the batteries.

Brett

[hermanmullins]

Lots of questions-- let's start with how the batteries are wired.

The chassis batteries (two 12 VDC batteries) are wired in PARALLEL. That is positive of battery #1 to positive of battery #2 to house positive. Negative of battery #1 to negative of battery #2 to house negative/ground.

House batteries (4-6 VDC batteries): Each pair of 6 VDC batteries is wired in SERIES to make "a 12 VDC battery in two cases". So House positive is wired to positive of battery #1. Negative of battery #1 is wired to positive of battery #2 and negative of battery #2 is wired to house negative/ground. Since you have two PAIRS of these, each PAIR is wired in parallel.

There is no way we can tell you where your charging system is failing without more information. Make sure the inverter/charger's breakers (on the 120 VAC breaker panel) are on. Make sure the resettable breaker on the inverter/charger (some inverters have them external, some internal) is ON/RESET.

Next, before plugging into shore power, measure voltage at the house battery with a digital voltmeter. Plug in and verify that the voltage rises-- unless batteries are deeply discharged, voltage should rise to 13.2 14.5 VDC. If it does not, check voltage at the inverter/charger.

And some coaches have both battery banks wired so they are charged by the inverter/charger, others are wired so that only the house batteries are charged by the inverter/charger. If the latter, you will need a trick l start, Echo charger, etc to charge the chassis batteries.

And, indeed, it is bad for a diesel engine to be started UNLESS you can drive it enough highway miles to get the oil (not just coolant) up to operating temperature. Anything less just adds a lot of moisture to the crankcase.

Brett

Great explanation on the wiring.

Brett, if this member is having both the house and the coach batteries going dead, it seems there has to be some sort of drag on them and his inverter is not keeping up or not working. If there is something dragging down both batteries down he might also have a bad isolator. The only thing on should be the radio/clock. When we had a drag on the battery (years ago) we would pull the fuse for the radio & clock. Remove the positive cable and jump between the post & cable. If it shows voltage, begin to remove fuses one at a time until the voltage drops to zero. Check what that fuse powers and correct the problem.

I like the idea of checking to voltage without power to the coach and then with power to see if the inverter is charging.

[wolfe10]

Great explanation on the wiring.

Brett, if this member is having both the house and the coach batteries going dead, it seems there has to be some sort of drag on them and his inverter is not keeping up or not working. If there is something dragging down both batteries down he might also have a bad isolator. The only thing on should be the radio/clock. When we had a drag on the battery (years ago) we would pull the fuse for the radio & clock. Remove the positive cable and jump between the post & cable. If it shows voltage, begin to remove fuses one at a time until the voltage drops to zero. Check what that fuse powers and correct the problem.

I like the idea of checking to voltage without power to the coach and then with power to see if the inverter is charging.

Herman,

Most inverter/chargers are wired directly to the house battery bank, not through a relay/isolator.

I agree, most coaches do have a parasitic draw on their 12 VDC systems-- both house and chassis battery banks.

BUT, since he is plugged in, the inverter/charger can and will easily keep up with the draw if everything is working as it should-- certainly on the house bank. And on the chassis bank as well IF it is wired to charge the chassis bank. Many are not wired to charge the chassis bank from the inverter/charger.

Brett

[Guest Wayne77590]

All the above.

There are so many varying configurations that it would be difficult to determine exactly what may be causing his depletion. A good way to try and determine is to first find out how much draw is on the system. Disconnecting a negative lead and connecting a current meter in series will tell you how much is being drawn from the system. It may be that your converter is not able to keep up. It may be a simple solution to isolate the offending "draw" on current. Once in-line you can start throwing switches to see if the current draw drops. The converter may keep up after that. Only time will tell.

In my case, I have to leave both battery disconnects in the "on" position to maintain a charge. I also turn off the step since there is a constant voltage across those terminals in my case. Since doing this I have not had a failed battery.

Do not give up on the batteries being bad. You could have one cell that is going bad and it will draw the rest of the battery down but total voltage may show good. Use a hydrometer and check each cell. They should be within specifications for that battery, and they should all be very, very close to the same reading. A hydrometer is a quick and dirty check. The best method is a commercial battery checker. Most auto stores have them and will check the battery for free.

Good luck.

[garykd]

Hi karaokegal,

Welcome to the FMCA forum.

While all the posts can be true, to start, let us keep this simple. If you own a digital volt meter and are comfortable using it do what Brett suggested.

Next, before plugging into shore power, measure voltage at the house battery with a digital voltmeter. Plug in and verify that the voltage rises-- unless batteries are deeply discharged, voltage should rise to 13.2 14.5 VDC.

If it does not, check voltage at the inverter/charger." And report back here with the results. We need to take this one step at a time.

If you are not comfortable using a meter, it is time to call a professional.

[jaselton]

Newbie here. We had our motorhome winterized and we made sure the master "disconnect" switch was activated so we believed everything was off. When we went to check on it after recent snow storm the steps went out OK. A few weeks later, we went back to get something out of MH and the steps went out only 1/4 of way and stopped. The engine would not start either. We jump started the engine and ran it for awhile, but the steps did not move.

All of the above info is very informative, but in a foriegn language for newbies like us. I think we need the professional, but which kind? Do we go to a battery professional, an inverter/charger professional (I read that manual, might as well have been written in Chinese) or just a regular RV repair shop? We live more than 50 miles in any direction from an RV repair place, so if we have to tow the motorhome there, we want to get to the right place first!!

I have learned a great deal from these forums and I thank all the experienced and knowledgeable people who respond here.

Judy and Jerry Aselton

Ellijay, Ga.

2006 National Dolphin LX 5355

2008 Jeep Liberty

[wolfe10]

Newbie here. We had our motorhome winterized and we made sure the master "disconnect" switch was activated so we believed everything was off. When we went to check on it after recent snow storm the steps went out OK. A few weeks later, we went back to get something out of MH and the steps went out only 1/4 of way and stopped. The engine would not start either. We jump started the engine and ran it for awhile, but the steps did not move.

All of the above info is very informative, but in a foriegn language for newbies like us. I think we need the professional, but which kind? Do we go to a battery professional, an inverter/charger professional (I read that manual, might as well have been written in Chinese) or just a regular RV repair shop? We live more than 50 miles in any direction from an RV repair place, so if we have to tow the motorhome there, we want to get to the right place first!!

I have learned a great deal from these forums and I thank all the experienced and knowledgeable people who respond here.

Judy and Jerry Aselton

Ellijay, Ga.

2006 National Dolphin LX 5355

2008 Jeep Liberty

First, tell us if you are plugged into shore power where you store the coach.

If yes and you have a "smart" charger or inverter/charger THAT HAS BEEN PROPERLY PROGRAMMED, it should keep the batteries up with no problem.

If no shore power, you will need to find some way to charge the batteries-- solar is a good option if stored outdoors.

Batteries naturally discharge with time, even with no load on them. Wet cell batteries do this self discharge faster than AGM batteries.

Another option if you are not going to use the coach this winter is to remove the batteries, take them home and perhaps once a week put a charger on them for a few hours.

Please, don't hesitate to ask questions if the language is not understandable.

Brett

[rorr1821]

I have a Monaco product so I understand your problem. First we need to determine what brand inverter you have (most likely a Magnum Energy but it could be Xantrex). Next, it is not clear to me if your house batteries or engine batteries are keeping charged or neither. If the house batteries are not being charged it is clearly an inverter problem, connection or the fuse between the inverter and battery bank is defective, because the house batteries are direct connection to the inverter. Also you need to check your monitor to be sure it was programmed for AGM batteries (not lead acid) and has the correct total battery AMP Hours for the batteries . For Example each 6 volt house battery is rated at say 200 AH and you have six batteries your total AH is 1200 divided by 2 or 600AH battery bank. This calculation is based on 6 volt batteries which is wired for 12 volt output.

If your engine batteries are not staying charged this is mostly due to the fact that Monaco was bad about not installing a functional circuit which would allow the shore power to charge both battery banks. Magnum Energy have a device called a battery combiner. It is a neat device which allows bi-directional charging and also has setting's to control charging of either bank. So if you are connected to shore power the house batteries are charged and after reaching a preset point (this is a setting you can control by manual setting on device) then it will allow up to 25 AMP to be passed to the engine batteries until they reach a preset charge point (again the manual setting's). While you are going down the road your alternator will charge your engine batteries and when they reach a preset point they will send 25 AMP charge to the house batteries until charged then cut off. This battery combiner will work with any inverter because it is independent of the inverter. It basically connected with 2ea 10 gauge wires going to both battery banks positive terminal with in line 30 AMP fuse on each leg, a common ground and it has an optional sense wire for better functionality. I recommend installing this optional wire. Also this device will not allow one battery bank to drain the other bank because it has built in points to cut-off the bi-directional transfer of amp's.

Maybe this will help. Good luck!

Ray

[rorr1821]

I forgot two other points. There is a possibility you have a bad cell in one of your engine batteries that could also contribute to your problem. Your lead acid engine batteries can be tested with hydrometer to check each cell or they can be load tested with a load meter. If you have Interstate batteries they have labels over the cell access ports. You need to take razor knife and carefully cut the label so you can remove the port covers with a screw driver. I have found over time these batteries will evaporate and the acid level will be at or below the cell plates. Interstate does not tell you this as a maintenance check because they market this battery as maintenace free. These ports are very small compared to the normal size found on normal car type batteries. As always use only distilled water to fill any battery.

Also you could have high resistance on one or several of your connections. If you have any corrosion, loose terminals, or loose wire connections to terminals it could be part of your problem. Monaco probably used for a six house batteries either 3/0 or 4/0 wire. They have in the pass used welding cable which has finer wire strands so they are flexible enough to move with a battery slide tray. Check to make sure they did not underside the wire. Also how far is you inverter from the battery bank. This is another factor used in determining wire size. As length of wire connecting battery bank and inverter increases so does resistance which requires the wire to be sized larger.

I have not read all of the replies so some of what I am saying may have already bend stated. I work on motorhomes as a retired person but I do claim to an expert. However, I have not had a problem that have not been able to fix. Happy Trails.

Ray