Battery on 25RES

[Steveo57]

It sounds like the battery is not fully charged when you start things up in the storage area. A fully charged battery should read 12.6-12.7 volts at rest.

[SiniWisdom]

I went to hook up the Cougar and the battery was dead. Since it would take too long to charge it, I disconnected it and took it to Batteries Plus to have them charge it and test it. I also bought a new battery and hooked it up to the Cougar so I wouldn't have to wait hours to start the trip. Since the original battery was a March 2019 battery (new), their load testing verified that the battery was good. That is how I got to the campground.

This is too complicated to try to explain. I believe there is something wrong with how the battery is hooked up in the camper, so I'll just talk to the Cougar dealer and have them check everything out. Thanks for everyone's advice!

[JRTJH]

I wonder if during all the 'battery connecting/switching/checking/troubleshooting" if you might have inadvertently connected the battery cables incorrectly (even momentarily) and blown the reverse polarity fuses on the trailer power center DC distribution panel ???

[SiniWisdom]

I was pretty careful about not doing that but if I had, would the interior lights work off the battery? Because they do, the fridge turns on, the slides operate... all without being plugged into outlet.

[JRTJH]

Originally Posted by SiniWisdom

I was pretty careful about not doing that but if I had, would the interior lights work off the battery? Because they do, the fridge turns on, the slides operate... all without being plugged into outlet.

Yes. The battery will work "just like it's supposed to" until it dies, then it will stop working. The converter will work when plugged into shore power to keep the lights and refrigerator operating, but the charge line to the battery is disconnected (through the blown reverse polarity fuses) so the battery won't charge at all.

The only indication you have that the reverse polarity fuses are blown is to physically look at them. Electrically, if you disconnect the battery and use a voltmeter on the battery cables, you'll get 0 VDC, but all the lights and 12 volt systems in the trailer will still be working.

[5J's]

Originally Posted by SiniWisdom

I don't quite undertstand "The next step would be to verify TV battery at the connector of the TV."

Sorry I'm late back to the game. I was referring to the 7 way plug on the truck.

[sonofcy]

Originally Posted by SiniWisdom

I went to hook up the Cougar and the battery was dead. Since it would take too long to charge it, I disconnected it and took it to Batteries Plus to have them charge it and test it. I also bought a new battery and hooked it up to the Cougar so I wouldn't have to wait hours to start the trip. Since the original battery was a March 2019 battery (new), their load testing verified that the battery was good. That is how I got to the campground.

This is too complicated to try to explain. I believe there is something wrong with how the battery is hooked up in the camper, so I'll just talk to the Cougar dealer and have them check everything out. Thanks for everyone's advice!

I don't see that anyone has asked you if the battery is a REAL deep cycle battery. If the battery says ANYTHING about cranking then it is at best a hybrid and can be quickly killed. If it has ever been fully discharged even once that could be the end of it. Experienced full timers use a GC2 battery. The pair of 6V batteries will last longer and have much more power. Our 5er came with 2 75AH 12 V batteries that I killed while trouble shooting a slide issue. I replaced them with a pair of Trojan T105's at 225AH but only use 50% so 112.5AH. It is highly unlikely the stores you are going to know anything about true deep discharge batteries and the RV dealer if he does won;t likely tell you unless he is going to sell it to you then you should ask why didn;'t you install one originally. I was just at a RV store/dealer and they had a wall of the wrong batteries. Nowhere do they have the right batteries. BTW, Trojan also makes the actual battery (not the case) for a few brands and are slightly cheaper. The way you know if you are at 50% is by installing a Bogart Engineering Trimetric TM-2030-RV meter or equivalent. Simple DIY job and now you will know EXACTLY what is happening with your battery. BTW, using a VOM to check voltage while connected in the RV is likely just reading your converter output, and taking it somewhere to test is better but the battery needs to rest some amount of time (1 hr?) to give a proper result.

[ddibon]

Lots of good replies here. These RVs have a large number of "phantom drains" of DC power. These drains discharge your battery unless the RV is totally shut down. The charging ability of your trailer pin or the built in converter is less than 3 amps. A Refrigerator, thermostat and propane alarm pull 2.1 to 2.5 amps. That means your battery will drop below 11.4 V in 4 to 12 hours (depending upon battery specifics), effectively shutting you down. Remember that the head unit for audiovisuals is DC powered. The AV unit is a mass consumer of DC power. A single, non LED light can pull 1.5 amps.

Such pulls on a low battery will also generate a lot of heat, further degrading your power system (Ohm's Law).

The fix so you don't have to learn crap beyond what it takes to enjoy your purchase is 2 fold. 1-Add more battery. 200 amp hours is needed for reasonable use. 2- Add a second battery charger/maintainer delivering 3 to 10 amps an hour. I use a 100W solar panel and battery tender set up. No issues for 4+ years.

[MRK&MRY]

Had a new awning installed at my local dealer. They turn the battery disconnect switch so customer battery won't go dead. I am new to a lot of this and didn't even know about the switch. "Accidently" spotted the switch while doing something else and all of my battery charging problems were solved!

[efrulla]

I have a 2017 25RES. I have always kept it plugged into household power. The first year I used a 15 AMP circuit. Last summer I had a 30 AMP Service installed. That way the battery is fresh before each trip and the fridge and other power soaks are not leaching off the battery but are being fed by the household power/

[Mainer]

TV alternators of ANY size are designed to maintain the thin plate lightly depleted starting battery at 13.6 volts, not to quickly recharge a depleted thick plate battery through 20 or more feet of smallish wire. To recharge a trailer battery that is down more than 20%, needs over 14 volts or it takes many hours to trickle charge it at 13.6 volts. Getting a full 13.6 volts to a depleted trailer battery is impossible with the size wire in the TV.

Even the converter in my Bullet won't put out it's bulk charge voltage of 14.4 volts for more than a few minutes unless the battery is way down because Keystone put the converter so far away from the batteries. It quickly drops to 13.6 volts at less than 5 amps and trickles it in.

Next mod is splitting the power panel from the converter and putting the converter forward nearer the batteries where it should be.

[SiniWisdom]

UPDATE:Service shop said the problem with the battery and the fridge is the converter, which they are replacing. I'm not totally convinced but we'll see I guess. Hopefully not when I'm stuck in the middle of nowhere! I did ask them if there is a way/room to add another battery and they are going to look into that. The battery compartment is small and I don't want to void the warranty, so again, we'll see.

[sonofcy]

Originally Posted by SiniWisdom

UPDATE:Service shop said the problem with the battery and the fridge is the converter, which they are replacing. I'm not totally convinced but we'll see I guess. Hopefully not when I'm stuck in the middle of nowhere! I did ask them if there is a way/room to add another battery and they are going to look into that. The battery compartment is small and I don't want to void the warranty, so again, we'll see.

You might be the rare person who has both a good RV shop and an accurate diagnosis but the odds are verrry long. If you check, you will see literally thousands of complaints about battery performance. Here are a few FACTS. Make sure you have a true deep cycle battery. You can tell it's the right battery if it does NOT have any labelling that says CCA (cold cranking amps), marine cranking amps, cranking anything. It should only list Amp Hours. Never use more than half the capacity. Get . Trimetric TM-2030-RV to know when you are getting close to half. A tow vehicle can not quickly charge a battery that is 20 feet away, the wiring is ridiculously small. Just look at the size of the wires coming off your battery and compare that to what is in the 7 pin RV connector. If you are going to analyze your battery by checking the voltage, you MUST disconnect all the positive or negative cables from the battery first. I have never seen an RV dealer install a proper battery. If nobody mentioned it already, get a pair of Trojan T-105's. Most factory installed converters are underpowered, too far away from the batteries with wires way too small. It only takes a small amount of voltage drop over skinny wires to make a huge difference in charging, we are talking about many extra hours at the low voltage the converter puts out. Total cost of a pair of T-105's and a TM-2030-RV is about $600 plus taxes.

[SiniWisdom]

I appreciate your input and advice, however, I am at the mercy of RV service shops because I am not a DIYer. I can install the batteries but only with the cables supplied in the Cougar. I'll look into the battery you recommend. I will start full timing about this time next year and over the course of this next year I am researching options that will make things easier living full time in this RV. Hopefully I can take some boot camps and seminars about RV maintenance and learning to do things by myself.
Thanks to everyone for your advice and input!

[chuckster57]

You tube is your best free on-line training, followed by this forum. Or the other way around LOL.