I wandered out to the coach today and heard what i thought was an animal chirping inside the coach. I went around opening bay doors looking for the source and when I opened the house battery door the MK gel cell batteries had a boiling sound coming from them. I went up and checked the monitor and it read 13.7 v 70 amps. I always keep the invertor off.
I have an infared temp sensor and the inner battery was 150F at the top and the outer was 82F. I am concerned something might overheat and cause bigger problems.
I have since shut off the Prosine charger/invertor switch. So have I lost a battery or two? Should I unplug the coach and unhook the batteries?
Dean
Thabks for posting this. The other day (about nov 12) I walked by the parts dept @ Nacogdoches and saw several bulged batteries on the floor just outside the dept window. At the cost of these, I hope we have good repor w/ the supplier. I would also be sure Foretravel has set the contro;s properly as when they changed mine the forgot to adjust the controller.
Get the hot battery out of the circuit!
Your charger is doing its job. BUT, if one cell in the battery is dead, it will be charging a "10 VDC battery" as if it were a 12. That SEVERELY overcharges/overheats the remaining good cells.
Brett I did seperate the batteries, and disconnected the ac power to the coach. I assume it's okay to reconnect just the one good battery for now?
I also assume that I should replace both batteries? These were installed in 2006 by MOT occording to the paperwork I have. Would have thought they should last a bit longer but don't know how they were previously used and maintained.
Dean
R.I am not sure this is in anyway related to what you saw at FOT, but my three large batteries for the house have bulges in the middle, all of them. I am told that is normal. They are gray, Deka brand, two years old. As for temperatures of the batteries, plugged in to shore and none are what you would call warm. Hope this helps you interpret your observation. FYI.
The critical thing is to KNOW how your batteries are being charged by either the inverter/charger or the engine alternator. Get the specifications from your particular battery brand and then use your multimeter (you do have one, right?) to determine the charging voltage from ALL charging sources. Overcharging WILL damage your pricey batteries.
Also, if your batteries do not have a battery temperature sensor connected to them I suggest that you purchase one and connect it to your inverter.
Regards,
I did check the charger setup a month or so ago and it was correct. I have not verified the charging voltage at the batteries so I am going to check it tomorrow.
I questioned the battery condition when I purchased the coach last March from FOT and was told they had been checked and were fine. ::)
I do have a temp sensor already installed and have checked it periodically and all seemed fine. I think the battery in question was going bad and just gave up recently.
I am just thankful I caught it when I did because I could smell the battery gas when I went in the coach and the battery compartment smelled pretty toxic as well. Don't want to think about what may have happened if It had kept boiling for a couple more days. I mean that thing was boiling hard and the caps were making a lot of noise venting off.
I did check both batteries with the multimeter after unhooking them and the hot one read 13.1V and the other was 11.7V. I will see where they are tomorrow and will hook up the hopefully good one and recheck the charging system.
Dean
While visiting Bill Chaplin three weeks ago in Arlington, TX, I had to replace a bad battery in our RAV4. We both noticed a peculiar smell when we stopped a couple of days before and looked everywhere for the source, brake rotors, etc. Not the typical sulphur battery smell at all. Finally pulled the car plastic battery cover off and looked at the battery. Was a bit warm so checked the voltage with the engine running and found it was about 14.5 volts but about 12.5V sitting. Bill took me down to the bat store, checked it with a load tester (was bad) and then replaced it. Voltage is fine now. Battery was the 2005 original battery. No other symptoms other than the high voltage and warm battery case temperature.
Goes to show that before you curse your alternator or inverter/charger, isolate each battery and use a load tester. A change in resistance can fool the regulator into overcharging. With a bank of two or three batteries, unless they are all pretty recent, best to replace all of them and use the old ones for cars, tractors, etc.
Pierce
Dean,
Yes, OK to reconnect the good battery.
And, yes, replace all batteries on that bank at the same time.
Thanks for the feedback.
So I quess my next research project will be for batteries. I think I will want to stay with Gels so any suggestions brand etc?
Dean
I am sure Wyatt will check in on this subject, but I did what he did (and he is the expert) and that is as you have Gel you may want to check your Alternator charging voltage when running around 1500rpm as you may find that while driving those gels are getting too high volts and that may be your battery undoing. I reduced mine and I have AGMs which are not as touchy as gels.
Like Jon Twok said , get the battery charging specs and check your inverter out etc.
John H
Interesting John. How did you go about reducing the charging voltage from the alternator?
I was hoping to get on this today but we have freezing rain coming down so it may have to wait.
Another question, What is the best, most accurate way to check the charger voltage? I have a multi-meter but should I check it with the house battery connected at the battery? I want to check the alternator voltage as well.....same method?
Just want to be sure I get this right before buying pricy new batteries...
Thanks, Dean
Hmmm, I just realized that my start batteries are Optima yellow-top AGM's and the house are MK 8G8D gels. Makes me wonder if the house batteries
have been overcharging from the alternator.
I also just checked the (disconnected) battery voltage again with my multimeter and the "hot" battery was 12.2v and the cool one was 10.6V
Doesn't make sense to me as I would think that the hot battery would be the bad one with lower voltage.
here is a link to some of that info. I hope Wyatt is reading the Forum soon to give you a "real' insight on what to do.
http://www.foreforums.com/index.php?action=search2 (http://www.foreforums.com/index.php?action=search2)
There is an article also on Beamalarm under--Alternator voltage changing, if yours is the same model.
I now know that you do not mix Gel and AGM as the Gel cannot take the voltage charge that AGM can. Gel are too finicky for my likingn and the ones that the coach came with also had bulging sides, mostly due to overcharging (battery store across from FOT told me) as I had to change one of my 3 at that time. That was a waste of money as it did not take too long to figure out that AGMs were the way to go once I got solar the following year. There is so much on the web about Gels being inferior and finicky that you cannot argue with it. Like I mentioned 6 months ago I spent a lot of time contacting many battery companies in US and Europe (by e mail) and almost all the Techs said AGM.
Brett say's in an article check both at Isolator and batteries and there should be a slight .5 volt drop at battery. That is were I check mine and do it at 1000rpm or more. Many points on this forum to look at just put "alternater charging" or similar in search box.
JohnH
John
I would only be guessing at to why the 12.2 is hot and the 10.6 is cold. And my guess is that the 12.2 is has shorted cells while the 10.6 is completely dead.
Like John, I switched to AGMs last year. Went with the East Penn (Deka) battery line because of ease of finding them locally. Nobody around here carries AGM batteries. Here is a good primer from East Penn concerning AGM and Gel batteries: http://www.dekabatteries.com/assets/base/1927.pdf (http://www.dekabatteries.com/assets/base/1927.pdf). Lots of good info concering the whys and wherefores of battery types and their uses. The Lifeline brand of AGM batteries are considered the cream of the crop. If you have a hard time finding them, check your local airport fixed-base operator. Lifeline has a big following with aircraft owners.
This is what I have done to get by for now. I checked both batteries with multimeter again. I agree with PatC that the 10.6 is dead. The other battery reads about 12.7 still so I have hooked it back up to the system and reconfiqured the charger to reflect one battery (220AH Verses 450AH).
The reading at the battery is 14.2V while charging from the house charger. So far so good. Then i shut down the AC power and started the coach. At 1200 RPM I got a reading of 13.9V at the battery from the alternator. Almost identical to what I get at the Yellow top start batteries.
Battery is staying about 50F which is a whole lot better than the 150F+ that I had last night. So I think the dead battery was trying to kill it's mate and causing the boiling etc. I will keep an eye on it for now until I can pick up replacement batterys.
I had AGM's in my last coach and liked them. I think I am in agreement that they may be the way to go. We do not dry camp a lot but do on occasion so don't need a huge bank of power. There is a Lifeline dealer not far from me that also carries Trojan batteries which I think are a close 2nd to Lifeline. He will also load test the existing batteries for free. I may have the start batteries tested too.
I will have to price them tomorrow (AGM's)to see how badly they will scorch the credit card. Will keep you posted.
Thanks for the input and suggestions. Dean
John good info checking voltage at the isolator. I will do that. I am curious what size AGM batteries you went with? I am also hoping to add some solar later on so would like to be mindful of that when I purchase the batteries.
Dean
I did just like the OEM in my U225. two 8D 12 volt. Hang on to you britches when they give you a price. I was amazed that my wife did not give me a hard time considering we had talked all the various options including going with 6 volt golf cart batteries. But she was very pleased on our last trip to Florida, being about to stop two time without plugging in, and having power to spare which included running the TV, computer, and my cpap breathing machine, which I remembered this time. Last trip had to have my son overnight it to us in Savannah. Miserable without the cpap breathing machine!
These look like the cats meow if I decide to get spendy on the batteries. Lifeline Batteries - Marine & RV Deep Cycle Batteries (http://www.lifelinebatteries.com/rvflyer.php?id=7)
Anywhere from $650. to $800. each depending on shipping or where you buy. Yep, not cheap at all....
Yup, been using Lifeline AGM's in sailboats and coaches for decades. Go to their website and look at the list of boat and RV manufacturers who use them as OE.
I have 3 8Ds for 775 amps and paid $500 each at AMSOLAR in Oregon but that was 16 months ago and I know they have gone up (Lifelines) I did look into Deka at East Penn but their casings are thinner wall and the plates are not as thick as Lifeline-hence the reason for buying Lifeline.
I do not have a problem lasting days (without solar charging and I never use gen') on them but have done a lot of changes to use less power and I have a residential elec fridge to run on them. Again I added the extra inverter for fridge and tv/stereo, so at night we are using less battery power just running this new inverter (1000w pure sine) compared to the big 2.5 Xantrex. I have this circuit rewired going thru a DPDT switch as per Beamalarm site of you know who!!!
John H
Well after much research and help from you good folks here I believe my battery troubles are over. I purchased 2 Lifeline GPL-8DA AGM batteries for the house. Now we have 510 CCA's. Had the MK's load tested and both were shot.
I had noticed that the start batteries were about the same vintage as the MK's so I pulled them out and had the battery shop test them as well. They were marginal at best. So I replaced the start's with Odyssey PC 1500 AGM's. Nice batteries. Two of the Odyssey's give me more CCA's than three of the yellow top Optima's. They are also Military spec. and have a better warrenty.
Lifeline Tech support was a great help when it came to re-configureing the Prosine charger for the new AGM's.
Cost me some bucks but I won't have to think about batteries for a while.
Dean
Are the start batteries you went with group 34m's (880cca)?
Thanks, Don
Yes they are Don. Actually you get 1500 amps (each) for the first 5 seconds. My battery guy claims they are the best battery for our application. The cost for 2 Odysseys was about the same as 3 Optimas.
Here is a link. PC 1500 DT Odyssey batteries (http://www.odysseybatteries.com/battery/pc1500.htm)
Dean
Thanks for the link Dean! Those look great and I have added them to my coach wish list. Hopefully the Optima's currently in there will get down the road a ways before they poop out...
Don