New House Batteries; no power

[SVBeachJB]

2008 Aspect 26A which, admittedly, has been sitting unattended (neglected) for the past 6-8 months due to medical issues. Planning a trip - engine battery fine, everything OK on shore power. I replaced the house batteries and get nothing. Suggestions where to start looking?

[Morich]

First we may need to get clear exactly what you mean!
When you say you get nothing, is that actually what you mean or do you mean you get nothing on the house battery items like lights, fans, etc?

Also does this mean really all the house items like the CO and propane detectors or only the parts which run through the battery disconnect switch?

The safety items still work when the switch is off but if those are also out, it means the problem is more toward the battery connections.

What do you know about the state of charge/voltage of the new batteries? Ifthere is not enough voltage there, the disconnect switch make not work to connect them!

More info needed!

[SVBeachJB]

Thanks Richard - exactly the type of guidance I need. No to lights, outlets, fans, control panel for slide, tank/battery levels and generator start. Also no lights or test response from either CO2 or Propane detectors. Both batteries register 5.9+v on multimeter. Newbie question - does the generator start off house or chassis battery? Thanks for your help. Battery connections are tight.

[Morich]

Okay, we can get started. One big thought is the voltage reading!
Are these the "normal" 12V batteries or has there been a change and you are using 6 volt batteries? A 5.9 on 12 volt battteries is very near totally dead but if there are two 6 volt wired correctly, they can be added to make them act as 12 volt. So we need to clear that question as a big thing.

But if they are either 12 or 2 six volt, we can do a couple things.
One is the generator does likely start using those batteries, so a very low may be the trouble there---still to be determined?

But there is a "funny" in the way the battery disconnect switch works and that may also be due to low voltage. When we store the RV and use the disconnect, we often think it will keep the batteries from running down, but the truth is that there are safety items like the CO and propane detctors that are never disconnected by the switch!

Good reason is they don't want the RV to fill with propane and no alarm to keep you from blowing yourself up! Good idea but makes it hard to figure on keeping things running.

Then to make it somewhat worse, the switch ties to a relay that is called a "latching relay". That means it moves when we use the switch to turn things on or off but it is a momentary switch which only works while we hold it. You may have noticed it doesn't click and stay when we press the switch?
So after we turn loose of the switch, there is a magnet gizmo inside the relay and after the relay moves closed or open, the magnet keeps it there. I suspect you had turned the disconnect switch off, the relay opens most of the power but there is one small breaker which stays powered and that ran the coach batteries totally down.
So we have to make sure there is good 12 volts to the switch and relay before it will move to close as we push the switch!

Do you have 12 volts or is it just 5.9? You can't close the disconnect untill it gets 12 volts or more!

One quick way to help if the engine will start is to start the engine and then try to press the switch to close the relay! When the engine runs, there is a "mode solenoid" which connects both the start and coach batteries together and the engine alternatonr is putting out good high voltage, so if the coach batteries are wired correctly, even if they are prettey near run down, the power from the alternator will begin working to charge them. It may take a minute or so but the disconnect and relay will soon get enough power to work.
Suggestions?
Check the question of 6 or 12 volt batteries and make sure that looks like they are wired right.
Then can you see a way to put a meter on the batteries and see it while somebody (got a helper?) starts the engine. If things are right and they rev the engine, you may see that 5.9 reading jump to around 14 volts.
I'm guessing without better info but I'm thinking the main problem is the coach batteries are run down and that stops most everything in the RV from working as the disconnect is not moving!
A battery charger on the coach batteries might be a good first move if I'm correct!
Do a little checking and tell us what's up?
No big thing, just confusing!!!

[Morich]

I was thinking 2 coach batteries but that looks like an option on your Rv,s o maybe only one for start and one for coach?
This is the drawing that shows two but ignore second if only one.

Click this snip to get a better view!

[SVBeachJB]

Yes, they are two new 6v Deep Cycle batteries for the coach; there is a separate 12v for the chassis/engine.Is the switch you're talking about the Aux/Batt switch by the door of the coach?

https://photos.google.com/photo/AF1QipPsU8Ofcvaz8JaG1xi-8zR3-Ha5FfMEYNoCgGyY[/IMG]

[SVBeachJB]

https://photos.app.goo.gl/NBxZfhKJt2byzght7

[Morich]

Yes, that is the switch.Winnebago has used different names and places at different times.
The big thing to know is that it doesn't disconnect ALL the things that can run the batteries down!

Check the voltages are right on thesepoints and that the two 6 volt are wired to add together to make it come out 12 volts?
Also a point that is easy to miss is the end of the ground that comes to the battery as it is often hidden and down out of sight!

[SVBeachJB]

Thanks! Will do and get back to you.

[SVBeachJB]

Doh! House batteries were hooked up wrong - short jumper went from pos > pos. Now hooked up pos on batt1 to neg on batt2, But only getting 5.92 on multimeter across both batteries. Can I put a 12v charger across both batteries to charge? BTW - house battery hookup was as it came from previous owner...

[Morich]

Originally Posted by SVBeachJB

Doh! House batteries were hooked up wrong - short jumper went from pos > pos. Now hooked up pos on batt1 to neg on batt2, But only getting 5.92 on multimeter across both batteries. Can I put a 12v charger across both batteries to charge? BTW - house battery hookup was as it came from previous owner...

Ouch! Small points can get big!
Yes, when wired correctly the two six volt should act the same as one 12 volt, so a charger will treat them the same. Connect at the 12 volt points, not on each battery alone.

The idea is that when we use two 6 volt we get more lead and acid involved in the storage and that means they last longer during use. Likely there are labels on the batteries which show the amp hour rating. That is how many amps we can pull out for an hour and the more, the better.

I've never gotten too involved in changing to try to get better long term use as we never got involved in dry camping without hookups. But where I have seen this done was in having one 12 Volt and swapping in two 6 volt.
Since it appears your specfic RV was built with the option of either one or two 12 volt, I might first want to look at how many amp hours the combo of two six gets me versus the combo of two 12 as the OEM plan called for.
Maybe some of the other folks here are more up on that factor as my last real battery thinking was a long time back!

But for short term, while the batteries get charged fully, the question of why none of the coach 12volt works, might be resolved pretty qick if you can get the batteries rewired to give near 12volt but run down.
Batteries take time to get the chemicals all through the batteries rearranged so we have to be careful when we do voltage tests. They can mislead us into thinking batteires charge much quicker if we are not aware.

When we put a charge of any sort, charger, converter, or engine alternator on a battery, it can appear that the WHOLE battery is charged if we read too soon. Reading while the charger is working, just tells us what the charger is putting out.
Charging, taking it off and reading right away, tells us what we call "surface charge" as it is just the effects of charging and just at the posts!

To get a true read of the voltage in the whole battery, we need to take the charge off and wait AT LEAST a couple hours, so that the chemicals and the whole batttery become stable. Sometimes compared to adding black ink at the hole in the top of a barrel? We add a teasoon of ink, look in the hole and it looks black but if we come back in a couple hours, we don't see any black as it has spread all through the barrel!
So don't trust what you see if you look too soon!

But if you can start the RV engine, that ties the start battery and the engine alternator together with the coach batteries and that big old alternator putting out lots of current will get the whole reading up prettty quick so that the inside 12 volt items and the switch may all begin to work---as long as the engine is running. You can test this by watching the voltage on the coach batteries and then when the engine gets moving, the voltage at the posts will jump up. If the engine is revved, you can often see the voltage go up and down in time with the engine speed! That's surface charge and will go away as soon as the engine is shut off but will likely be enough to make the aux battery switch move the relay and make things work inside!

There could be other things that have corroded, etc while settting but getting good battery is the first point to make the rest work!

[SVBeachJB]

Another Newbie question - Should the house batteries be hooked up in series or parallel?

[Morich]

Series for using two 6 volt to get 12 volts!

That's where I might question the use oftwo six volt, rather than two 12 volt??

Two six will get the 12 volt needed but possibly no more amp hours. Using two 12 volt in parallel gets the 12 volt but twice the amp hours!

Some info here:
https://www.batterystuff.com/kb/arti...-tutorial.html

[SVBeachJB]

Not sure why the previous owners had 2x 6v, but just kept it that way due to not knowing any better. We are most often connected to 30A shore power, or at least 15A, so it's not a huge issue. Thanks for the link.

[Morich]

Lots of discussion and theories but not something I've bothered with much due to no need for me and my use.
Part of the idea is fine in that the golf cart batterries are true deep cycleand made to allow tobe run down furhter without damage when compared to lots of 12 Volt which are a "hybrid" of deep cycle and start type battery. That means if you have two 12 volt combo deep cycle/start like is often used for trolling motors on fishing boats and you have the room to place four six volts, you can run them much longer.
It's all in the way the batteries are made and what we want to do with them. For our use, we went through the years of tent campers and less comfort as we gradually upgraded and got more spoiled. Now we always look for water and electricity as a basic level, so how to get the longest use of coach batteries is not something we get involved in doing.
There is no way way to make things work and it can take years of trial and error before we get it straight and about that time is when we totally quit the RV /camping!

[SVBeachJB]

Agree - not doing much boondocking - closest is a friend's driveway with at least an extension cord...

[SgtB]

Originally Posted by SVBeachJB

Another Newbie question - Should the house batteries be hooked up in series or parallel?

It depends on what they are; 6V or 12V

[SVBeachJB]

They are 6v, so series, I assume.

[SgtB]

Originally Posted by SVBeachJB

They are 6v, so series, I assume.

Yes, two 6V in series will give you same amps but 12V. Two 12V in parallel will still give you 12V but double the amps

I have always preferred to use 12V batteries in place of the 6V that many manufacturers install in their new rigs. That gave me many more amps than I could get out of that same number of 6V batteries in series. When I bought this current rig used I swapped the four 6V's for four 12V's. Your choice, but need to make sure the system in the rig can handle the change. Others on here can have talked about what you may need to change or do. And I have always used Interstate or Trojan pure deep cycle batteries in my RVs and boats for trolling motors. As many have pointed out many battery's are listed as deep cycle but are not. One c usually tell by the price. Those are my thoughts, others may disagree.

[SVBeachJB]

Thanks for the input. Since I've just replaced the 6v batteries, I'm going to stick with them until the time comes, and then decide whether or not to go 12v.