Just Want to Clarify House Battery Charge Issue

[Sky_Boss]

HELLO ALL!

I think I have a good handle on some house battery charging issues and cured some real problems. I'm a bit paranoid about my house batteries getting drained so forgive me if I am asking a really basic question.

I understand that my converter will charge the batteries on genny or shore power. If I am going down the road and have the genny fired up to run the air conditioner I will probably also run my refer on electric at the same time. I believe that in this configuration I will need to engage the AUX BATTERY switch which makes sense to me. The genny puts out 110 to the converter and the converter charges the house batteries.

During the times I am not needing to run the genny then I know I will need the refer to be on LP. I also know that the refer needs 12V service to run the control board.

So a couple questions:

1. Do I still need to activate the AUX BATTERY switch to get 12V to refer for for any other 12V circuits for that matter?

2. Does the chassis alternator also charge the house batteries so that running the AUX BATTERY switch (if needed) will not drain my house batteries?

STILL LEARNING

[bluepill]

Are you referring to the "Aux. Battery DISCONNECT" switch near the entry door?

[Sky_Boss]

Originally Posted by bluepill

Are you referring to the "Aux. Battery DISCONNECT" switch near the entry door?

Yes sir.

[Skip426]

De-activating the "Aux Battery " switch will cut power to all 12v circuits in the coach. So leave it on; or the Fridge won't operate on 110; shut down for storage is the only reason to turn "Aux batt " switch off.
I've run with gen set on for roof A/C operation on the highway and the convertor and alternator, don't seem to have any issues working together. Not sure if your coach would do the same, but I'm sure all manufacturers would forsee this and wire things up accordingly.
Driving the engine alternator should charge all batteries in the coach, if your coach batteries go down while driving, you may have a problem with the "Dual Battery Isolator" or whatever system in use in your coach.

[Sky_Boss]

Originally Posted by Skip426

De-activating the "Aux Battery " switch will cut power to all 12v circuits in the coach. So leave it on; or the Fridge won't operate on 110; shut down for storage is the only reason to turn "Aux batt " switch off.

...

Driving the engine alternator should charge all batteries in the coach, if your coach batteries go down while driving, you may have a problem with the "Dual Battery Isolator" or whatever system in use in your coach.

That is how I think I understood the use of the AUX BAT switch.

I'm just a tad concerned that my house batteries are a little smallish. I ran the rig on batteries for about 2 hours with no lights on, refer and HWH on LP and 2 Fantastics running. According to my EMS my batteries were down to 12.2V. I get a little squeamish when I get below 12.2V and perhaps that is a result of dead house batteries in the past that were later found to be caused by my converter. That problem has since been fixed and no problems since.

Without going to far off topic, how low of a voltage is it safe to let a house battery drop to before one must fire up genny/shore power to top them off again?

THANKS!

[RV Wizard]

12.2 vdc is a commonly used standard of a lead acid battery state of charge to be at 50%. You don't want to go below this level for good battery maintenance.

[siggyd]

To be sure,I would clip on a Volt-meter to the RV batteries and then test with the Genny,Engine,Shore power, Aux switch On & OFF.
That will answer and confirm all your questions ,in case there is a problem
with some other failure.
Siggy D.

[Dr4Film]

Originally Posted by athuddriver

HELLO ALL!

I think I have a good handle on some house battery charging issues and cured some real problems. I'm a bit paranoid about my house batteries getting drained so forgive me if I am asking a really basic question.

I understand that my converter will charge the batteries on genny or shore power. If I am going down the road and have the genny fired up to run the air conditioner I will probably also run my refer on electric at the same time. I believe that in this configuration I will need to engage the AUX BATTERY switch which makes sense to me. The genny puts out 110 to the converter and the converter charges the house batteries.

During the times I am not needing to run the genny then I know I will need the refer to be on LP. I also know that the refer needs 12V service to run the control board.

So a couple questions:

1. Do I still need to activate the AUX BATTERY switch to get 12V to refer for for any other 12V circuits for that matter?

2. Does the chassis alternator also charge the house batteries so that running the AUX BATTERY switch (if needed) will not drain my house batteries?

STILL LEARNING

After reading all of the posts on this thread someone is really confused or Fleetwood does things A$$ backwards or they use weird nomenclature.

An AUX Battery Switch is not the same as a Battery Disonnect Switch. The battery disconnect switch is commonly called the "salesman switch" which is usually near the entry door and it disconnects 12 VDC to the interior of the coach. The AUX Battery Switch as I know how it is primarily used is to temporarily tie both battery banks together when one bank is low. Such as in this case, if the chassis battery was too low to start the engine, you hold the AUX Battery Switch until the engine starts.

I don't know how Fleetwood put together its charging system but I know Monaco did NOT install total charging systems on every coach that would allow both battery banks to be charged when using shore or genny power or when the engine alternator is running.

However, there are after-market devices that will work if the coach isn't already equipped. A good one is called Trik-l-Start that will keep the chassis battery charged while on shore or genny power.

Ultra TRIK-L-START Starting Battery Charger/Maintainer

My coach is equipped with a Lambert Battery Maintainer which will keep both battery banks charged when using any power supply.

Regarding how low you can let your house battery bank go down to, that number is between 11.9 - 12.0 VDC. That's when the AGS should kick in and charge your battery bank back up. The battery state for full charge is Float Status.

Here is a good article on 12 VDC batteries and maintenance.

The 12volt Side of Life (Part 1)

Dr4Film ----- Richard

[jauguston]

12.2v is considered the 50% SOC for your flooded lead acid batteries BUT there are conditions that have to be met before the reading you get with a volt meter is anywhere near accurate. There has to have been NO LOAD of any kind on the battery bank for several hours and no charging done for the same length of time. Otherwise the voltage number you see is meaningless. The batteries need to be disconnected as there are usually phantom draws you don't even know about. Removing a cable from the pos battery post is the most sure way to know there is no draw on them. Its never easy (-:

Jim

[Gary RVRoamer]

Since athuddriver has a Winnebago, I think he can safely ignore the remarks about Fleetwood electrical designs or what Monaco does or doesn't do. Winnie has their own way of doing things. And I doubt if athuddrive's Adventurer has an AGS to automatically kick the generator on.

The battery disconnect switch should be left on (batteries online) all the time except when the coach is being stored for several or more days without being plugged to shore power. It should also remain on while driving, since the engine alternator will be charging both house (Aux) and chassis batteries.

It appears your batteries are draining rather quickly. That suggests either a large power draw even when you think there is "nothing on" or batteries that are in poor condition. I would suggest a battery load test at a local auto parts shop to rule out bad batteries. The test is usually free.

[ChasA]

What Gary said is right. I think of it this way: If the switch is off, the batteries are disconnected and cannot be charged from any source. You can still have 12 vdc power from the converter if you have shore/gen power-- even if the switch is off. So if you want your house batteries to be charged the switch must be on. Hope I haven't added to the confusion.

[wa8yxm]

I see nobody answered the second question you ask.

Both answers are the same: YES.

Aux battery is another name for the HOUSE battery, power to interior lights, fridge, water heater control, water pump and a host of other things.

[RV Wizard]

Not all coach builders will run the refrigerator circuit through the house battery disconnect.
This allows you to be able to turn on the refrigerator for an upcoming trip and still have most everything else turned off.

[Ottav]

Newbie here..
So if you turn off the aux battery switch located near the entrance and are plugged into
shore, will the interior lights light..

Bob