An ignorance question

SmokeyBear-JAY

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Location
CLOVIS CA
It has become obvious my converter is dead or dieing. It is either not sending power (amps?) to the battery or not enough to keep the battery charged or not enough to charge the battery and run the refrigerator. I suspect the latter as it will keep the battery charged at home when plugged in to shore power with nothing on. I have been on the road, staying at campgrounds since the 9th. The refrigerator started showing low battery light today.

Fortunately, I brought a 3 amp battery tender/charger with me. My question is: Is it OK to keep the battery tender hooked to the battery while on shore power? Or would that be unwise?

The battery is a LA, 24V. Not sure about that last number as doing this from memory.

Everything I'm describing is while on shore power. Since the 9th, I have probably been off shore power 9-10 hours while driving. Has been on shore power since about 3 pm the 11th. All other systems, including microwave - are working fine.

Thanks.
 
I forgot an important fact. This is to be a stop-gap measure until I get home on the 24th. Please, I need some advice on this before the food in refrigerator starts to go bad.
 
Well it can't be a 24v battery. Must be a group 24 which relates to size not voltage. I have seen a battery charger used to prop up a failed converter a few times so anything to prop up the battery may keep the fridge cold. I would have the battery tested at an auto supply store and that will eliminate that as a cause.
 
Yes, you can leave the battery charger on the battery, even if the converter is working. There are no issues with doing that. If you leave it on, it “might” be able to charge up the battery with enough time. If you can, also plug the TT into your truck. Leave engine running, and it will also charge the battery.
 
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Well it can't be a 24v battery. Must be a group 24 which relates to size not voltage. I have seen a battery charger used to prop up a failed converter a few times so anything to prop up the battery may keep the fridge cold. I would have the battery tested at an auto supply store and that will eliminate that as a cause.
It's a group 27. 12 volt, deep cycle, Intestate, purchased and installed 5/24.
Yes, you can leave the battery charger on the battery, even if the converter is working. There are no issues with doing that. If you leave it on, it “might” be able to charge up the battery with enough time. If you can, also plug the TT into your truck. Leave engine running, and it will also charge the battery.
Thank you for your answer. The battery tender/charger seems to be doing it. Refrigerator is now working. We'll see how long. Hopefully long enough to bring thee temps back down.
BTW: This is a Class C forum, so no TT and truck to hook to. If I run the engine, will that also charge the house battery?
 
We camped with a friend whose converter died the first day out. He connected it to a battery charger and it worked just fine until we left to return home. A rebuilt converter made it whole again!

Most manufacturers' offer rebuilt units at a deep discount.
 
Sorry Smokey! I saw 1997 Eagle 222 and incorrectly thought Eagle 5th wheel. That means with the engine running, you should be able to charge the battery’s. Not cheap to do, but will get you going when you need it.
 
The trickle charger shouldn't cause any problems but probably not give you the charge you need. Have you measured the battery voltage while plugged in? This will tell you what the converter is doing. Should read mid 13s to mid 14s while charging. If it stays in the 12s, the converter isn't doing anything. Check its circuit breaker for the heck of it.

Converter Voltage.JPG


Voltmeter 2.JPG
 
The trickle charger shouldn't cause any problems but probably not give you the charge you need.
So far it seems to be working. I'll check again in the morning. Hopefully the refrigerator is still on.
Have you measured the battery voltage while plugged in? This will tell you what the converter is doing. Should read mid 13s to mid 14s while charging.
Yes. It wasn't even 12. More like 7
Check its circuit breaker for the heck of it.
I can't find a circuit breaker labeled Converter.
 
7 volts means completely discharged. Be sure and have the battery load tested before you need to depend on it.

If you can, post a picture of the converter including the chart of circuits on the door. Mine has "Converter" labeled as AC Branch Circuit 'F'. I'm guessing you don't see *any* tripped breaker? You could just flip 'em all if you wanted.
 
Thank you pconroy. I was flat on my back yesterday and couldn't do anything. Having a bad back ain't for sissies.

A did a search and found I had posted on this subject 3 or 4 different times in the last 2 or 3 months, trying to determine what the problem is. You, and others, have been most helpful. It's now obvious to me the converter is bad. What had me confused is it would fully charge the battery when hooked to shore power in storage, but not when plugged in at a campground with the refrigerator on. Finally, the light went on in my head and that's why I started this thread to find out if my stop-gap idea is ok. Seems it is. I will continue this until I get home next week. Since this is way beyond my pay grade (ignorance, again) I have an appointment to take it to my local RV repair place where I have all my house repairs done. I trust them. A lot. They have always been square with me.

BTW: If you are still interested, there is a photo of the converter in this post.

PS: I really like the search feature in this new forum software. It seems to me to be more user friendly.
 
I'm confused. Are you saying your converter is keeping your battery charged when plugged in at home, but not while plugged in away from home?

Also, just to be clear, the converter should provide 12V power to your rig when plugged in to shore power, while charging up the battery at the same time. Then when you unplug, the battery should be providing 12V power up to its storage capacity. That's why several people have mentioned putting a volt meter on the battery terminals while plugged in, and while unplugged. This would be an easy first step in diagnosing a converter/battery problem.

Additionally, if you've run that battery down to 7V (which is well past "dead"), you've likely done permanent damage. You can really only get away with that a handful of times at best before you short a cell and the battery becomes "bricked". In my experience, AGM deep cycle batteries can tolerate more deep discharges more often than a flooded-cell unit. Though that's not a "hard and fast" rule. I did have a high quality AGM short a cell in my wife's truck pretty early in its life... But that's what warranties are for...
 
Yes it fully charges battery when plugged in at home.

Yes it does not keep battery charged when plugged in at a campground.

The difference is at home refrigerator is not on, when at a campground the refrigerator is on using 120v because plugged in. My hunch is the 12v drain from the refrigerator is more than the voltage the converter is providing.
When I "boost" the charge using the battery tender it eventually comes back to full charge.
 
the refrigerator is on using 120v because plugged in. My hunch is the 12v drain from the refrigerator

Not trying to pick apart the posts, but I'm positive your fridge is 12V, not 120V. Regardless, I've been seeing that and thinking it's a red herring. The 'fridge isn't part of the problem.

But...

Have you (a) plugged in at Campground AND (b) turned OFF the 'fridge then checked the voltage at the battery?

If you're campground plugged it, the fridge is off -- and you see 13.2V or better at the battery, then by-golly the fridge seems to be part of the problem.
 
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The other thing that's puzzling is "everything works when plugged in at home" and "does not work when plugged in at campground."

That's throwing me for a loop.

Have you tried to see what happens when you're on generator power?
 
Whew, okay, I'm glad I'm not the only one confused.

If your battery is getting charged when you're plugged in at home, but not when plugged in anywhere else, well, that's just downright confusing. I wouldn't even know where to begin with that, if it's even possible...

The fridge is likely a 2-way absorption fridge, which uses a 120V heating element when plugged into shore power, and propane for heat when not plugged into shore power. It always uses 12V to run the "electronics".

You said that you measured your battery at 7V (or something much less than 12V), which indicates you do own a multi-meter. You need to plug the rig into shore power, and measure the voltage across the battery posts. Write that voltage down. Then go unplug your camper, and wait about 5 minutes, and take the battery measurement again, and write that number down. Then fire up your generator (assuming you can), wait about 5 minutes, and measure at the battery again.

Good readings at the battery would be:

Plugged into shore power or generator running: 13.2-14.4V
Unplugged from shore power: 12.2-12.7V

If those are the readings you're getting, see below for the potential for enough voltage drop in the 12V fridge wiring to cause it to give a "low voltage" alarm.

If you're getting anything less than 13V at the battery when plugged in to shore power or generator running, then you have an issue between the converter and the battery. Could be a loose wire, could be a blown fuse, could even be a bad converter. Next step in that case would be to go back to the converter and take voltage measurements in and out; you should be getting 120V into the converter, and 13.2-14.4V out of the converter. If you're getting less than 120V into the converter, then you need to continue up the chain there (there should be a wire going into a standard 120V outlet, than feeds from a slot in your AC breaker panel). If you're getting less than 13.2V out of the converter, then you need to check the fuses on the converter. If the fuses are good, but you're still not getting 13.2-14.4 out, then you might be looking at a bad converter.

If you're getting anything less than 12.0V when unplugged, after you've been plugged in for a while with the converter charging the battery (which you verified by taking a measurement at the battery while plugged in), then you likely have a battery issue.

Now, all of that said, there is a situation where you can be running in "propane" mode, and the fridge is not getting enough volts. But IIRC that happens regardless what your power source is (converter or battery), and it's because the wire gauge that was used for constant 12V to the fridge is not appropriate for the length of the run. So you'll get such a drop in voltage that the fridge won't get enough, and it'll show a "low voltage" error, even though each source may have plenty of volts & amps to dole out.

Only you can gauge your comfort level with actually conducting repairs, but if I were you, I'd stay out of the 120V AC system. If you find a problem there, probably best to hire a professional. But the 12V DC system is not quite as dangerous until you start replacing wires and making connections. A wire not gauged properly, or a loose connection can cause things to melt and catch fire. Which can happen in the AC side as well, but that side can also kill you pretty quick...
 
The fridge uses both 12vdc and 120vac when on the power grid.
When on gas it's only requirement is 12vdc.
Keep us posted when you get the converter looked at! A poser for sure!
 
The fridge uses both 12vdc and 120vac when on the power grid.
When on gas it's only requirement is 12vdc.
Keep us posted when you get the converter looked at! A poser for sure!

Ah!!!!!! You (two) are correct. I misspoke!
Thank you (both) for correcting my error.

When I see 120V fridge, I immediately think residential, not absorbtion.
 
Works while plugged in at home but not at campground. Do the 120 volt items (microwave, AC) work at the campground? If not, then the power at the campground is suspect. I assume you use an adapter at home to change the power cord plug into a standard 120 volt plug. Do you have 30 amp or 50 amp in your rig? If 50 then maybe the leg that feeds the converter is missing.
 
I’m guessing that you are using a dog bone at the campground that you are not using at home. Or as Jim said, an issue in the pedestal.
 

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