Is a 2000 Itasca Spirit Converter Charging Normally or Are the Batteries Bad?

[ApplianceGuy]

Hello all,

I am happy new owner of a 2000 Itasca Spirit 31' class C. The seller always had the RV on shoreline power, so I have no idea how good or bad the AUX batteries are. What I do know is, the shoreline cord was pulling 4.5 amps (on a killowatt meter) for battery charging. I found the aux batteries low on water and making sizzling sounds.... I filled them with distilled water. They held charge fine overnight (I disconnected everything overnight).

Today I am playing with the batteries again, and still the charging circuit is pulling 4 amps (and seems to be slowly dropping in rate), batteries are not boiling or sizzling (at least not yet). My question is, is 4 amps a normal number for battery charging? Seems high to me, I hooked up my Noco Genius battery tender/charger and it only pulled 0.5 amps, and said the batteries were OK and done/ready after only 20 mins or so.

Also, the charger/inverter behind the circuit breaker/fuse box makes a electrical buzz/hum sound when the charger circuit is running. I'm sure it's normal but I don't like the sound. Is my 2000's era charging system still decent and acceptable to use in 2026?

Thank you!!!!!

 

[klook]

You are pulling 4 amps AC power which is a ten times factor to charge DC. Watts law is W=V*A Your NoCo cannot put out that many amps so it doesn't pull as much on the AC side. I think the Genius is a 5 amp max charger, mine is X2....There may be other things drawing amps also on the AC side. Humming on old units is normal. Let the batteries rest, disconnected, not hooked to anything. apply a light load briefly and then take a reading, the voltage should be 12.7/12.8. This will test the batteries. To test the charger, hook it back up and you should see 13.1 or close which is a float charge. Give it a little time after hooking it up. Then decide if you need a new convertor.

 

[Morich]

But if you start with basics, the batteries are one of the most basic and they are highly suspect if things are as described!
Folks who leave Rv plugged in for years will go through batteries very quickly. When you hear batteries, they are likely toast! If they sizzle, they are not charging, they are boiling off water! Exposed plates mean bad battery!
But there are always different ways to go about testing. I find current to be really hard to get meaningful answers when dealing with RV as there are so many variables. Under normal conditions the load changes a bunch. Add in batteries that are likely ruined and telling what the converter should be doing is just too difficult for me to consider when voltage coming from the converter is a very handy thing. If the batteries are gone, they may look like a dead short to the converter, so I would want to verify batteries are good, then make sure the voltage going to them is good before moving too far in any direction.
What specs does a 25 year old converter have? Does it have three stages or just on/off when it senses battery low voltage? Owners manual seems to say it is simple two stage but that is often good enough if we don't mistreat the batteries by leaving it plugged in full time!

 

[klook]

So what was your advice to him? Give up and hire a professional .....like me? I have fixed dozens of these situations and could figure it out quickly if I was onsite. But he has to start somewhere. I suggested testing the batteries first? I agree they are most likely toast. Perhaps I should have told him to find a load tester.....but then, a professional has one.
Lets start here. Battery Basics - Guide to Batteries | BatteryStuff
He didn't ask for a college level class on battery specifics. I have seen many of these old convertors working just fine, they were well made. Once he tests his batteries and finds them bad, even if he takes them to a auto store, we can move along in his questions.

 

[ApplianceGuy]

I think the Genius is a 5 amp max charger, mine is X2....There may be other things drawing amps also on the AC side. Humming on old units is normal. Let the batteries rest, disconnected, not hooked to anything. apply a light load briefly and then take a reading, the voltage should be 12.7/12.8.

Yes, i've seen the genius pull more amps on dead batteries, but it's treating these batteries like they're fine.
I tried the disconnected volt test overnight, but I did not put any load on the battery This morning before testing. 12.9 at rest without any preload

With the onboard charger running i'm seeing 13.6, 13.7v

And i'm doing all these tests with zero load... fridge turned off and not a single light running. With the inverter breaker off, it's pulling 0 amps.

But if you start with basics, the batteries are one of the most basic and they are highly suspect if things are as described!
Folks who leave Rv plugged in for years will go through batteries very quickly. When you hear batteries, they are likely toast! If they sizzle, they are not charging, they are boiling off water! Exposed plates mean bad battery!

I was thinking the same as well. In my limited experience with these water filled deep cycle batteries, they might read good after fresh charge, but they're probably trash After a few days of rest. Being that the previous owner was on a shoreline cable for three years and never looked at the batteries, i'm wagering they're probably cooked. See photos

 

[ApplianceGuy]

Having that all said, what is the economical way to fix this up? What would you guys do in my shoes? Not exactly trying to break the bank, but i'm open to a different type of chemistry battery if it works with the factory inverter/charger

 

[Morich]

Okay for step by step, I would first get the batteries tested. Whether that is simply watching them as they perform or letting a parts store do the test is their choice.
The converter is low on my suspect list, althought there may be newer which do a better job as they have three stages of charge over the two stage type.
But converter change is not one I jump to easily if other things are not checked first.
Batteries that make noise is an easy one for me to jump to assuming they are bad! So I would do the easy, most suspect item for several reasons. Pretty sure to get the right answer, ease and lack of expense to test, and then when item one is pretty sure to be correct, maybe then add the converter question to the mix and do some voltage testing under different situations and maybe it's good, or maybe face the bigger issues involved in changing the converter to a newer model.
But when not totally sure of what and how the RV electrical sytems work, we often hear about lots of confusion, so that can take a bit of time and steady thought.

Just the idea of what the "battery cutoff" switches do can warp lots of people's mind.
Just the idea that cutting off the battery to keep it from draining may not cut off the safety items but DOES cut off the charge can give lots of heartburn!

One reason I don't favor current testing on RV when we are not really used to them is how easy it is to find we have current flowing but not realize that things are hidden away and using power in sneaky ways!
Way too easy for the lightbulb under the steps to be drawing power and us not see it in the daylight! Hard to spot the LED on detectors is still on if we don't really do a good look!

 

[Morich]

Sorry got interupted! What I see is a battery that needs cleaning and checking the connections. There is way tooo much chance of a small leak running through the film on top of the battery! Those battery clamp are often ground! so if there is a high resistance throught the film, you can easily have a "leak' frompositive post to ground and it constantly works to runn the current flow up even while letting the battery go down!

Lithium is a nice upgrade for coach batteries but it has lots of stuff and expense to get it done right. If a big boost in the dry camping powe ris not high on the list, it can be more than I would do! Almost certain to need a different charger to get the max benifits.

 

[Morich]

I failed to actually answer the main question about what to do on batteries. While lithium can be great, it ican be expensive, not only for th ebatteries but also to get the best use of them, it takes other changes. One is the lithium do best when they can charge faster and to a higher voltage than lead. To get that, it often requires a different converter. then the OEM RV setup has a system to connect the chassis and coach battery when the RV engine runs. This is good for puttiong some charge back into both groups but with a problem. Lithuim can take a high charge rate and that menas much more current may flow out of the engine alternator.
Enough higher that it may overheat and fail? Any kind of overheating is kind of a question on how much and how often before it fails?
Several different wasy to deal with it but the total of all the semi-large probelsm can add up to not being with it to some. I have never doen it on our RV because we no longer go where we don't have water and that often means we also have power, making having a great battery system not worth it for us.
If battery work is not a common thing for you. it is not hard but it needs to be done often on lead acid due to the water we lose and the fumes we get.

If I were looking at new batteries, I go for AGM as a deal that doesn't require any other changes, so the price difference is only slightly high for the batteries.
AGM has the BIG advantage for me of less work. The water/acid stays in the battery!
No refills needed!
Also fumes to corrode everyting in the area are near gone!
So we can trade a little more money up frot but since the batteries don't run out of water to damage them, the AGM may last much better than lead if we are not almost sleeping with them to keep them in good shape!
I think I see two six volt battyeries there? I might look at using two 12V for cutting the work down if when a change might be needed?

It's the old story of what each of us finds works best for us for what we do and what we want to spend?? Lots of options and none work for everybody!

 

[ApplianceGuy]

Thank you for the detailed response. I've checked all the connections etc, I didn't find any loose cables, nor do I think there is an inverter problem.... i'm mainly concerned it just keeps on running pulling 4 - 4.5 amps for the batt charging, with an annoying hum, and seems with no end in sight. It is eventually supposed to ramp down the charging once it is "happy" with the batt charge?

The info in the Winnebago/Spirit owners manual has nothing about charge rates, or theory of operation. So I appreciate all the info I can get, to better understand this. Thanks again!

 

[Morich]

The manul is short on how things work but it does mention the converter will not come on until the battery gets down to some specific point, if it finds that point really low, the converter will chargeat a high rate until the battery reaches a better level at which the charging backs down slightly until reaching the final voltage they spec. When it senses full charge the converter turns off until the battery again goes down to the starting level.
To me this says the converter should be "kicking off" when reaching a certain point and then kick on again!
Maybe easier to get a mental picture of a pump which kicks on when a barrel of water gets to a low point? the pump works hard if the water is really low and then slows as the barrel gets full. Finally the pump shuts off and waits until the water is down to a certain level.
But what might be happening if there is too much leaking across the top of the battery, say from a positvie post to one of the battery clamsp, the converter may never feel like the battery is getting full to the shut off point.
No real idea of the logic of the converter but possibly it is not shutting down because it is still sending power and it is going somewhere besides the battery?
Once way that might be happening is through the film on top of the battery as it looks like there is only like an inch between one positive post and that nearby clamp.
That "leak" might also be why you are seeing sucha high amp reading?
My first thought would be to clean the battery top with a mix of baking sada and water, swabbed on with a paint brush and then cleaned with water and wiped down to dry. This needs to be doen with both battery cables off and the clamp removed to avoid any kind of short when working the baking soda/water around the posts.
It could just be bad batteries but before I go for new, I like to make sure!

Small point? No need for lots of baking soda but like a teraspoon in a quart will make it alkaline enough to clear any remnants of battery acid on top. Just wanting to neutralize any acid up there and not wanting to leave traces of baking soda!
I've long forgotten any large amount of chemistry but acid on top will conduct electricity and you need to clear any doubts like where all that power is going! Basic idea is that power moves through the acid inside the battery but does the same when it is on top and forms a path!

I spend 12 years of my main job cleaning batteries and I never learned to like it! We had to wipe down and clean the batteries every month and I was super glad to start getting AGM and lithium in my sites before I retired!

 

[klook]

It would appear you have 2 6 volt batteries. A load test is the only way to know how good the batteries are. Go to Harbor Freight and get their load tester. Follow the instructions. As to the convertor, it is working. But you may want to invest in a modern one that charges more "smartly". If you get one that also will charge lithium, you will be ready to change but that opens another can of worms for later.

 

[ApplianceGuy]

Thanks, klook! I will go get one of them testers. The batteries are holding up decently well for the little bit i've been playing around. What exactly are the onboard batteries meant to handle.... just lights, simple electronics, and startup of generator? Occasional pumps for a few minutes at a time?

 

[klook]

All things in a camper except the microwave and tv are at least controlled by 12v. The furnace is all 12v, the water heater is controlled by 12v, the AC is controlled by 12v. All lights, and fans and Water pump.

 

[ApplianceGuy]

All things in a camper except the microwave and tv are at least controlled by 12v. The furnace is all 12v, the water heater is controlled by 12v, the AC is controlled by 12v. All lights, and fans and Water pump.

So... if I go into a remote place with no hookups... the idea is I can run the water pump, LP heater, fans, all low voltage stuff maybe for a day or two, without running a noisy generator? And then for AC or microwave, I need to fire the generator up?

 

[Morich]

Are you a guy that can get at least some value in electrical drawings?
I assume appliance guys do that!
So to get a good set of drawings, this site is good for your Winnebago Spirit:

Wiring Diagrams

The plan Winn uses shows the schematic type labeled as "drawings" for the different groups. Then if needing more about WHERE things are located go to the "installation" drawings!
They use chassis for the "truck" the RV is built on and "body" as the part Winn adds on top!
To see the wiring for the RV/body 12VDC, this should get it:

https://www.winnebago.com/Files/Files/Winnebago/Resources/Diagram/2000/132245.pdf

They stamp wire ID on small wires and match them to drawing info:

To "decode" the labels, this list works but a bit irritating to scroll?

https://www.winnebago.com/Files/Files/Winnebago/Resources/Diagram/electrical_guide.pdf

Better to run the list through a system to make it searchable but I did it once and now have no idea how!! But it gives loots of info like from and to locations for wires and that can often be chased back to find if it it battery or ground and which fuse or breaker!

I find I lack motivation on a lot of things I no longer use!
But it may be a big help to a guy who has an RV figure out and repair!
Good luck on the trek!

 

[klook]

Yes. The furnace is the biggest draw as it has a blower and control circuitry. Lead acid will only allow you to use 50% of the amp hours you have. They charge slower. Drawing them below 50% will damage them. That is around 11.9 volts. That is why you have 2 6 volts in series. Its really 1 big 12v battery. More lead makes more amp hours.
With 300 amp hours of Lithium and only the 1000w inverter running my fridge and charging a few items like phones and hearing aids on 12v, and the furnace with the thermostat set to 65, I would wake up to around 72% left. I think 2 days is dependent on how much each thing runs obviously. Mostly how cool it is outside. If you have the classic absorption fridge, that uses 12v for controls and propane can be used instead of 120v.

 

[klook]

Some of it you will learn from doing it. That was much of the why for my trip out west this winter. I knew about solar, I had camped a bunch and boondocked a little, without solar. But I set myself up with what I calculated I needed with plans to purchase more as it worked out. I came back realizing how much I needed to do what we want to do. Running the AC is out of the question. I want to make coffee in the morning and use an instapot and airfryer. I know what I need and am purchasing the last components this spring.

 

[Morich]

On the recharge for lead acid, keep in mind how tricky and how slow they are! If run down and you start the RV engine or genset to recharge, it is easy to run it for a hour and turn the charging off to llok at the voltage. We may seee it as 13 volts and jump to think we have great batteries! WRONG! that is called surface charge and it is just kind of like a puile of electrons right at the post that have not moved on down and spread all through the different cells!
If we run 6 hours and it charges up in an hour, we can get faked into thinking we can do the same the next night but find out the batteries die in two hours! That is because it was not at all fully charged! Charging is a slow 6-8 hour process!
Bummer to let the generator or engine run for that long, so better to not go there!
Beware the tricks they can play!

 

[ApplianceGuy]

Are you a guy that can get at least some value in electrical drawings?
I assume appliance guys do that!



I find I lack motivation on a lot of things I no longer use!
But it may be a big help to a guy who has an RV figure out and repair!
Good luck on the trek!

This is what a good forum is for.... exactly what I needed. THANK YOU!!!