select Member Services on website to join

Author Topic: House Battery Charging  (Read 761 times)

Jeff Watt

  • BAC Member
  • *
  • Posts: 110
  • Thanked: 10 times
House Battery Charging
« on: April 20, 2019, 11:40:31 PM »
On my way home from Texas, I noticed my house batteries were not being charged while driving, i.e. being drawn down. As I have a residential fridge the inverter is on while driving. In the past, the alternator would keep the batteries charged even with the draw of the fridge and some other things including charging the battery on my TOAD (Explorer) - I ran 12v power to it from house rather than chassis.

No problem charging batteries when parked on shore power (batteries fully charged when leaving in morning) or when using the genset. Was seeing (on the Alladin) a fairly consistent draw between 14-26amp discharge while driving - which seems higher than it should be. Consequently, to avoid drawing them down too much and to ensure the TOAD battery was being charged, I used the genset.

Is this a problem with the BigBoy or the BIRD units? Or something else. I tried using the battery combiner switch a couple of mornings but nothing changed. On an aside, doing so didn't seem to help starting. Maybe its bad as well.

Thanks

Jeff
Jeffrey Watt
2007 Patriot Thunder Hanover, C13

David T. Richelderfer

  • David, Leslie & JB
  • BAC Member
  • *
  • Posts: 1116
  • Thanked: 306 times
  • 2004 Marquis Sapphire 45, 505 hp C-12
Re: House Battery Charging
« Reply #1 on: April 21, 2019, 12:22:16 AM »
If the inverter/charger using either shore power or generator power is charging both the house and chassis batteries okay, then my guess is the Big Boy/BIRD is working okay (at least in one direction).

Thus, my guess is the engine's alternator is not getting power to the chassis batteries.  We had to replace our alternator several years ago after starting the engine with the six house batteries low.  Between charging the chassis batteries and the house batteries, it's too much demand for the alternator.  The alternator overheats and blows a diode.
« Last Edit: April 21, 2019, 04:04:38 AM by David T. Richelderfer »
David, Leslie & JB
Towing a black Chevy Avalanche
Using a Blackhawk Towbar & Evenbrake
RF Mogul Eagle 3 for DISH TV
Go Beavers, OSU Class of '71
RVing since 1973
Constitutionalists, Golfers & Capitalists
Your luck is the residue of your management

Frank Bergamo

  • BAC Member
  • *
  • Posts: 97
  • Thanked: 14 times
Re: House Battery Charging
« Reply #2 on: April 21, 2019, 02:31:00 AM »
Jeff, with coach running, check the voltage on the two big terminals of the Big Boy, if working properly, they should be the same or close to it. Looking at the Big Boy, the big terminal on the left comes from the alternator, the one on right from the generator/shore power. If voltage is not the same, start the coach, check the left big terminal. It should be in the 14 volt range. If it is, the chassis batteries should be charging, the alternator is working properly. Then, turn ignition off and start generator. Now check the big terminal on the right, it should be in the 13.8 volt range. If it is the house batteries should be charging. By doing this it will isolate the alternator vs. the generator charging systems. If you are not getting the proper readings on each side of the Big Boy, the Big Boy or the circuit board that the Big Boy is connected to are the problem. Here is a link that will help you. http://beaveramb.org/forum/index.php/topic,7961.msg55211.html#msg55211 Just went thru this with my coach, by cleaning the terminals inside the Big Boy, system started working properly. Hope this helps.
« Last Edit: April 21, 2019, 10:43:33 PM by Frank Bergamo »
Frank & Paulette Bergamo
2019-       : 2007 Marquis Topaz IV  C-15 600 HP Allison 4000
2014-2019: 2002 Marquis Emerald C-12 505 HP Allison 4000
2004-2014: 1986 Executive Diplomat 3208 250 HP Allison MT-643
Grand Junction, CO.

Jeff Prupis

  • BAC Member
  • *
  • Posts: 206
  • Thanked: 30 times
Re: House Battery Charging
« Reply #3 on: April 21, 2019, 03:02:24 AM »
Had the same symptom this summer in Canada - was the alternator.
La Dolce Vita
'05 Beaver Monterey Ventura II
CAT C9 400HP
'06 Jeep Liberty

Jeff Watt

  • BAC Member
  • *
  • Posts: 110
  • Thanked: 10 times
Re: House Battery Charging
« Reply #4 on: April 21, 2019, 09:30:33 PM »
David, house batteries were charged when leaving in morning so alternator wasn’t trying to recharge depleted batteries.

Jeff, I’ll check what Frank suggest first before checking alternator. It seems to be charging the chassis batteries though.

Frank, the right terminal will show 13.8 or so if on shore power or generator? Will do some sleuthing tomorrow,

Thanks.

Jeff
Jeffrey Watt
2007 Patriot Thunder Hanover, C13

Scott Shearer

  • BAC Member
  • *
  • Posts: 29
  • Thanked: 14 times
Re: House Battery Charging
« Reply #5 on: April 21, 2019, 10:49:18 PM »
Jeff,


You can use your Aladdin system to do some basic troubleshooting (actually, you already have).

Before you break camp, with shore power connected (charger charging) and the ignition key in the on position (engine not running), compare Battery votage on the Engine/Trans screen (chassis batteries) to the House Bat voltage on the Coach Electrical screen. Both should be in the mid 13 volt range and should be within ~.5 volts of each other. If the chassis batteries are less than the House Bat voltage (i.e. 12.3 volts) your BIRD system is suspect. As Frank mentioned, could be a corroded Big Boy.

You can make the same check while driving, your chassis batteries should be >13.3 volts and, again, both battery banks within ~.5 volts of each other. If your chassis battery voltage is low you may have a bad alternator.

If you find that your BIRD system is suspect, cycling the Big Boy relay with the battery boost switch several times might clear any corrosion enough to get you home. That's assuming that the Big Boy is engaging but not connecting the two battery banks together. You'll need to be disconnected from shore power, engine and generator off and the Big Boy disengaged.

Scott
Scott

2006 Patriot Thunder
Lexington IV 40'
Cat C13
2015 JKU Hard Rock

Jeff Watt

  • BAC Member
  • *
  • Posts: 110
  • Thanked: 10 times
Re: House Battery Charging
« Reply #6 on: April 22, 2019, 12:46:42 AM »
Scott,

It’s been plugged in by the house since Wednesday night, so should be charged up.

I just did as you suggested while plugged in and from the Aladdin, the house batteries are at 13.5 and the chassis batteries are at 12.8 - 12.9 (fluctuating).

From memory (did a lot driving last week), the chassis battery readout was always in the 13.8-14.1 range. House batteries start out at ~ 13 but fairly quickly started to drop to 12.8 and would have continued to drop; reason I started generator. They (4) are 5 yr old 4D AGMs so may be suspect. Chassis batteries are 6 years old and I’m thinking they are getting tired just the way they turn the C-13 over.

Will try the battery connect as you describe. I did it before but while plugged in.

Jeff
« Last Edit: April 22, 2019, 12:54:55 AM by Jeff Watt »
Jeffrey Watt
2007 Patriot Thunder Hanover, C13

Jeff Watt

  • BAC Member
  • *
  • Posts: 110
  • Thanked: 10 times
Re: House Battery Charging
« Reply #7 on: April 22, 2019, 01:45:45 AM »
After my last post I started to wonder if the chassis batteries are weak thereby causing the alternator to continuously try to charge them and therefore are not charging the house batteries?
Jeffrey Watt
2007 Patriot Thunder Hanover, C13

Steve Huber Co-Admin

  • Administrator Group
  • *
  • Posts: 2215
  • Thanked: 1300 times
Re: House Battery Charging
« Reply #8 on: April 22, 2019, 02:09:08 AM »
Jeff,
Suggest you pull your chassis batteries and check them to eliminate that variable.
Steve
Steve
2015-          07 Contessa Bayshore C9,  400 hp
2013-2015: 00 Marquis Tourmaline, C12, 425 hp
2005-2013: 01 Contessa Naples, 3126B, 330 hp
The following users thanked this post: George Harwell

David T. Richelderfer

  • David, Leslie & JB
  • BAC Member
  • *
  • Posts: 1116
  • Thanked: 306 times
  • 2004 Marquis Sapphire 45, 505 hp C-12
Re: House Battery Charging
« Reply #9 on: April 22, 2019, 03:37:08 AM »
Jeff - Your 4:45 post today explains to me that the BigBoy/BIRD system is not working.  That's a different explanation as I interpret it from a day or two ago.  As I understand it, if your engine is running, then the alternator should be throwing over 14 volts to your batteries, both battery banks.  Thus, when driving down the road after some period of time (an hour or so), both the house and chassis battery banks should be showing over 14 volts.

When parked and either plugged in or with the generator running, your inverter/charger will go through the three charging states starting with BULK, then ABSORPTION, and finally FLOAT.  Once the house battery bank has charged to above 13.1 to 13.3 volts, then the Big Boy/BIRD system should kick in to allow the inverter to also charge the chassis battery bank.  After the inverter status goes to FLOAT following BULK and ABSORPTION, then both the house and chassis battery banks should be showing 13.6 to 13.7 volts until a discharge occurs.
« Last Edit: April 23, 2019, 12:24:33 AM by David T. Richelderfer »
David, Leslie & JB
Towing a black Chevy Avalanche
Using a Blackhawk Towbar & Evenbrake
RF Mogul Eagle 3 for DISH TV
Go Beavers, OSU Class of '71
RVing since 1973
Constitutionalists, Golfers & Capitalists
Your luck is the residue of your management
The following users thanked this post: George Harwell

Gerald Farris

  • Past President
  • Board Moderator
  • *
  • Posts: 2024
  • Thanked: 728 times
    • Farris Journey Across The USA
Re: House Battery Charging
« Reply #10 on: April 22, 2019, 02:32:22 PM »
Jeff,
The logical reason that your engine is not turning over as fast when starting is that the chassis batteries are discharged from sitting with the constant 1.5 amp drain from your ECM if your "BIRD" system is not working. So, do not waste your time and money replacing batteries until you repair your "BIRD" system. Hopefully, it is just a corroded Big Boy solenoid, but you need to properly diagnose the system to determine that.

Gerald
2002 Solitaire (2017 -  )
2000 Marquis, C12 (2004 - 2017)
1993 Patriot  (2000-2004)

Jeff Watt

  • BAC Member
  • *
  • Posts: 110
  • Thanked: 10 times
Re: House Battery Charging
« Reply #11 on: April 22, 2019, 10:25:01 PM »
Gerald, David.

Thanks for your advice. I’ll have a look at the BigBoy first. While it’s not urgent since we are home, and as we’re not planning on going anywhere soon, nevertheless it’s on the To Do list.

Just to double check, Frank says the left terminal is alternator; right is shore/gen?

Jeff

Jeffrey Watt
2007 Patriot Thunder Hanover, C13

Gerald Farris

  • Past President
  • Board Moderator
  • *
  • Posts: 2024
  • Thanked: 728 times
    • Farris Journey Across The USA
Re: House Battery Charging
« Reply #12 on: April 22, 2019, 11:57:52 PM »
Jeff,
While it might seem like there is no time pressure to repair your "BIRD" system, there is one thing tat will cause an issue if it is not repaired unless you use a work-around to keep the chassis batteries charged. The parasitic drains on your chassis batteries will completely discharge them, and therefore damage them unless there is a charging source to keep them charged. Chassis batteries are not like your house batteries when it comes to discharging and recharging. If you deeply discharge and recharge the average chassis battery 3 or 4 times, it is damaged beyond any usability. So either fix your "BIRD" system or use an alternate charging device for your chassis batteries until you do.

When it comes to which side of the Big Boy your 2 battery banks are connected to, I would use a volt meter to verify the location of each circuit, because not all of these coaches are wired the same, even with the same year and model.

Gerald                                     
2002 Solitaire (2017 -  )
2000 Marquis, C12 (2004 - 2017)
1993 Patriot  (2000-2004)

Jeff Watt

  • BAC Member
  • *
  • Posts: 110
  • Thanked: 10 times
Re: House Battery Charging
« Reply #13 on: April 24, 2019, 03:40:20 PM »
Gerald, others,

Apologize for slow response, busy getting settled back in.

Out of curiosity I disconnected from shore power and waited about 15 minutes. Then checked battery and from the Aladdin the readings are:

Chassis batteries were at 12.6 with ignition on.
House batteries were at 12.9 but had a 6amp discharge even though nothing, I believe was left on.

Hooked back to shore and then house batteries showed pretty big charge of over 30amp and reading of 13.4v. This, again was after maybe 20 minutes. I think they need to be checked as well.

All readings off of Aladdin, so probably not totally accurate.

Has been nice here but cooling off below freezing over night in the next couple of days, so I’ll be putting it in the heated shed. Can work on it then.  I may put a charger on the chassis batteries.

To remove and clean or replace the  BigBoy, obviously disconnect and no genset, and do I disconnect battery switches?

Just for interest, if the BigBoy has failed or failing I assume it happened on the trip home as the coach was sitting for 3 months in Texas and fired right up a few days before we left, albeit with the usual initial slow crank, then faster and start.

Thanks as always,

Jeff
Jeffrey Watt
2007 Patriot Thunder Hanover, C13

Steve Huber Co-Admin

  • Administrator Group
  • *
  • Posts: 2215
  • Thanked: 1300 times
Re: House Battery Charging
« Reply #14 on: April 24, 2019, 05:22:26 PM »
Jeff,
Yes, make sure both battery switches are off as the batteries are wired directly to the Big Boy terminals through the switches. I also disconnect the + from the batteries to remove any possibility of a short or arc. When reassembling the Big Boy, be sure the O ring is in good shape as it prevents moisture intrusion.
Steve
Steve
2015-          07 Contessa Bayshore C9,  400 hp
2013-2015: 00 Marquis Tourmaline, C12, 425 hp
2005-2013: 01 Contessa Naples, 3126B, 330 hp