Batteries ka-put our first time out

[OTRA15]

Originally Posted by avonroemer

The 9 step list is great BUT #8 says to charge for 48 hours and I would caution that you need to monitor the batteries almost constantly while charging. I left mine overnight and found them boiling in the morning. Ending up taking them to Interstate for a full replacement as they were less than a year old and then ordered a PD converter replacement because I don’t trust myself to prevent this in the future.

Welcome to the forum! A night or two of charging with the OEM charger should not have caused the damage, even with batteries that are fully charged. The battery water was probably low already IMO. Are you sure the converter was operating correctly?

Or one (or more) cells of one (or two) batteries were already bad IMO.

Cheers,

Peter

[avonroemer]

As the unit is only 6 months off the lot I had not checked the water level, my bad, so it could have been low. I had not been on battery power much and mostly had been on shore power when parked at the house on a 30 amp receptacle. Meter on the wall showed charge rate of 13.7 volts. Bad cell in both batteries was the same one. No telling what went on while the unit was on the dealer lot, but I doubt it was on shore power all the time. Guess I am just lucky they croaked within the first year so Interstate replaced them.

[uncle_bob]

Originally Posted by avonroemer

The 9 step list is great BUT #8 says to charge for 48 hours and I would caution that you need to monitor the batteries almost constantly while charging. I left mine overnight and found them boiling in the morning. Ending up taking them to Interstate for a full replacement as they were less than a year old and then ordered a PD converter replacement because I don’t trust myself to prevent this in the future.

Hi

Your new converter will do *exactly* the same thing if a cell shorts. It's what all converters do in this case. Like it or not, batteries do have defects. That is one of the reasons the battery dealers are so familiar with swapping them out.

Why don't we hear a lot of repeat stories? You dump the defective batteries and the odds are in your favor on the next set. You can get bad ones two times in a row, it just doesn't happen very often at all.

Some math:

If one in 100 batteries coming off the line are bad.

If you use them in. pairs and the pair dies together (which it does).

You have about a 1 in 50 chance of trouble.

If you buy two sets in a row, your odds of both sets being bad are about 1 in 2,500

This of course assumes you don't do something nutty. Most people get the lecture on what not to do after the first failures. That essentially eliminates user error on the second set. The odds go up even further as a result.

Bob

[Lljones07]

We had a similar situation on our maiden voyage with our 2017 Classic. Unbeknownst to us, faulty electric hookup at a campground in Vermont blew the charge fuse. No indicator. So our first night at our next stop; New Hampshire, the battery died. Replaced the fuse and things got back to normal. We’re fortunate to have great support from our dealer, Ansley RV in Altoona, PA.

[Msherw]

OEM batteries (any brand) are unbelievably unreliable now. As Uncle Bob said, 1 in 100 are probably bad out the door. Couple that with sitting on a lot for a while, low water levels, single stage converter and you are likely to get a bad day.

I invested in an AGM battery - expensive but zero maintenance (ok so someone will have a bad remark about AGM but it beats the wet cells). Think about AGM if you solar charge.

[geta356911]

My advice, even though my Airstream is a 1971, get a 100watt solar panel with the good controller, you will never have to worry about dead batteries, even while in storage!.
True, you could have had a bad set of batteries,or a bad controller. HOwever, a cheap solar setup, will provide an alternative charging source. (think dry camping too)

GT

[WhereStream]

Originally Posted by Lljones07

We had a similar situation on our maiden voyage with our 2017 Classic. Unbeknownst to us, faulty electric hookup at a campground in Vermont blew the charge fuse. No indicator. So our first night at our next stop; New Hampshire, the battery died. Replaced the fuse and things got back to normal. We’re fortunate to have great support from our dealer, Ansley RV in Altoona, PA.

Charge fuse ... where might I find such a thing in my Airstream?

[xrvr]

Yes, interested in what the charge fuse is.

[Coach B]

When we picked up our brand new 27FB this spring I noticed the next day the batteries were hot while hooked up to shore power. I checked the acid level and it was below the top of the plates. Took it right back to the AS dealer who did a load test and replaced both batteries. Yes, they were Interstates. Those are typically good batteries but I've seen several people post similar stories that makes me wonder who isn't filling the batteries.

[Mrs. Bale]

I had a similar issue and there was a simple fix. I checked the breaker box and one of the switches had flipped when the campground electrical blew the surge protector. I flipped the switch and was back in business.

[Mrs. Bale]

Sorry! I responded to the wrong post

[Mrs. Bale]

Check the circuit breaker box. I had a similar problem and it was a simple matter of resetting the switch

[billrector]

Originally Posted by Coach B

When we picked up our brand new 27FB this spring I noticed the next day the batteries were hot while hooked up to shore power. I checked the acid level and it was below the top of the plates. Took it right back to the AS dealer who did a load test and replaced both batteries. Yes, they were Interstates. Those are typically good batteries but I've seen several people post similar stories that makes me wonder who isn't filling the batteries.

I've been to two AS dealerships in TX and both have them out in a yard, battery connected, not plugged in. We all know that there are parasitic loads that will take the batteries down to below the 50% level within a week. I believe the dealers don't worry about the batteries and just charge them up a day or so before you arrive to pick up your new AS (with damaged batteries).

On our maiden voyage, every morning when we woke up the batteries would be below 12V even though they were fully charged the day before with both solar and generators. We stopped at NAPA who tested our batteries and called them good. However, they were being charged by the 7 pin connector just prior to arriving at NAPA so that could have made a difference.

Airstream dealers don't care as Interstate replaces the batteries and eats the cost. I called AS about this and they said that they have talked to dealers about delivering the AS without batteries, but dealerships insist on batteries being included from the factory.

[uncle_bob]

Hi

If you are charging the batteries via the 7 pin connector, it will take about two weeks (if ever) to get them up to a full charge. You can't put much current though the 7 pin and the TV voltage regulator "cuts back" fairly quickly.

Testing a battery at the store *should* involve putting a load on it and seeing what happens (voltage and current wise). You then charge it up and check it a second time. If it takes charge and delivers to a load, it is indeed a good battery.

If you run a battery down in a day, one or more of the following is true:

1) You have way to much load on the battery ( = you have the inverter turned on maybe).

2) Your charger is not powered up / not connected ( = fuse or breaker is blown maybe)

3) Your use / store switch is wired such that you are not charging in mode it is set to.

4) You are not charging long enough to actually get the batteries "full". ( = it takes about 20 hours on charge)

5) One or the other battery is actually not wired into the circuit.

Simple way to check things:

1) Put a multimeter on the battery. It will read something < 12.6V with no charging going on.

2) Plug in shore power. The battery voltage should rise quickly. It may or may not be above 12.6V quickly.

3) Come back in a four hours (while still charging). The voltage should be above 13V.

If all that checks out, your charger is doing it's job and it's hooked up.

4) Leave the charger on for 24 hours then disconnect shore power.

5) Come back in two hours, the battery should read above 12.5V at 70F

Yes, solar messes things up a bit. The "disconnect shore power" also needs to turn off solar if you have it. Plan for things happening when the sun is not up in the sky

If it appears you are not charging, what is the state of the use / store switch? If it's in store and no charge, put it in "use" and see what happens. Some trailers get wired so that is the only way the converter / charger hooks to the batteries.

If you are relying on one of the stock panels in the trailer to tell you when the battery is 100% charged, that's a bad mistake. They are just looking at voltage. They can not tell you what's going on as you charge.

Lots of fun !!

Bob

[Mollysdad]

Originally Posted by WhereStream

At one point, however, on our second day at the campground (which had no vacancies ... every site taken) the surge protector turned off power to the Airstream. I could not get the power to work without removing the surge protector.

If the surge protector turned the power off, then the voltage was too low or too high. With a full campground, probably too low. It's dangerous to things with motors like an AC unit, because the unit will draw the correct watts, making up for low voltage by drawing high current. Too high and the motor burns out.

Batteries not charging? Sounds like the converter was not doing it's job.

I'm not sure about your history with the unit. Is this your first trip? Or did you have other successful trips?

Just because a unit is a 2017 doesn't mean the batteries are new. It may have sat on the lot for 9 months, rarely plugged in. Or plugged in 24/7 and boiled off the water.

First, I'd take the batteries home and check the water, then specific gravity if you can. Voltage, with no load is misleading.
Simpler, take it to a Interstate Battery dealer and let him check them for free.

[Al and Missy]

It is my understanding that the testing provided by auto parts places tests only the ability of the battery to deliver cranking power. A battery with internal leakage but is otherwise good will test good for cranking power but will discharge in a short time. The best way to test capacity is to fully charge the battery and put a known load on it for a time. Most battery manufacturers of deep discharge batteries publish the capacity at one or more discharge rates. Ideally the owner test would mimic one of those rates so a comparison could be made. Example - Trojan Group 27 battery, 117 Ah at a 100 hour discharge rate - 117/100 = 1.17 amps. While not ideal, an approximation load would be a 10 ohm, 20 watt or higher resistor. Time how long it takes to get the battery to 50% capacity (12.1 volts at no load). It should be close to 50 hours.

Al

[uncle_bob]

Originally Posted by Al and Missy

It is my understanding that the testing provided by auto parts places tests only the ability of the battery to deliver cranking power. A battery with internal leakage but is otherwise good will test good for cranking power but will discharge in a short time. The best way to test capacity is to fully charge the battery and put a known load on it for a time. Most battery manufacturers of deep discharge batteries publish the capacity at one or more discharge rates. Ideally the owner test would mimic one of those rates so a comparison could be made. Example - Trojan Group 27 battery, 117 Ah at a 100 hour discharge rate - 117/100 = 1.17 amps. While not ideal, an approximation load would be a 10 ohm, 20 watt or higher resistor. Time how long it takes to get the battery to 50% capacity (12.1 volts at no load). It should be close to 50 hours.

Al

Hi

A battery with a *really* high self discharge rate will drop 20% of it's capacity in a month. No, that's not a typo, the dimensions are months. That's why it is impractical to test quickly in a shop.

If you go shopping for resistors, a 2:1 power derating is the normal approach. The why of this gets a bit crazy, but that's generally how it's done. The "easy" way to do a discharge test is to grab a load you already have (old headlight bulb maybe). Tack it on the battery and check the DC current with your clamp amp meter. The "exotic" way to do it is to buy one of the "shop grade" battery chargers that include a load function along with a paper tape readout of what's going on.

Keep in mind that to do a "full capacity" test, you need to take the battery to zero. That's likely to damage it. Going to an assumed 50% point at 12.something volts is only a guess. You need to know a bit about the battery chemistry and the internal temperature to be sure of the magic voltage. You also have the issue of measuring the voltage under load. At the end of all this you are still only left with a rough idea of what's going on....

Bottom line - weird virus infections of batteries are fun to talk about. In 99.999% of the cases they aren't the issue. The problem is something much more simple. Most of the time it's user error. No that's not much fun to talk about. It can be hard to spot if you aren't right there watching everything that is being done. Pretty much nobody does something they *know* is wrong and then complains about the result .....

Bob

[squirower]

When connected to shore power or generator, the battery display indicates charge going to the battery, not the actual charge of the battery. Detach from external power source and turn the battery switch to “use”, and you will get that true charge reading on the battery. If you leave the switch in the use position when the battery is fully charged and connected to external power, it will be boiled up the an overcharge. If charged and not being used, it must be in the “store” mode. However, there seems to be no way to isolate the batteries from charging when hooked up and underway, so charging is constant when towing. Buy a Voltmeter and check your charge often so there’s no confusion. You then know when to charge or not. Had the same problem you did, and just figured it out by trial and error. Properly charged, you can run everything except the heat pumps on battery only for several nights - lights, furnace, sound system and TVs (with inverter on). Even when in the garage I check batteries and if below 10 volts, charge them overnight and store.

[billrector]

Originally Posted by uncle_bob

Hi

If you are charging the batteries via the 7 pin connector, it will take about two weeks (if ever) to get them up to a full charge. You can't put much current though the 7 pin and the TV voltage regulator "cuts back" fairly quickly.


Bob

Agree! I wasn't so much implying that the battery was fully charged by the time I got to NAPA just that the batteries had been under charge. I'm assuming that you really need to wait a few hours after ANY charge before testing the batteries?

[OTRA15]

Originally Posted by squirower

When connected to shore power or generator, the battery display indicates charge going to the battery, not the actual charge of the battery. Detach from external power source and turn the battery switch to “use”, and you will get that true charge reading on the battery. If you leave the switch in the use position when the battery is fully charged and connected to external power, it will be boiled up the an overcharge. If charged and not being used, it must be in the “store” mode. However, there seems to be no way to isolate the batteries from charging when hooked up and underway, so charging is constant when towing. Buy a Voltmeter and check your charge often so there’s no confusion. You then know when to charge or not. Had the same problem you did, and just figured it out by trial and error. Properly charged, you can run everything except the heat pumps on battery only for several nights - lights, furnace, sound system and TVs (with inverter on). Even when in the garage I check batteries and if below 10 volts, charge them overnight and store.

If you let your batteries get below 12.2 volts or 50%, you start to affect their lifespan. At 10 volts you have probably done serious damage IMO. Please start at the beginning of this thread and check the various resources linked, like the NW Battery School:

http://www.batteriesnorthwest.com/batteryschool.cfm

Also, more than one night of using the furnace will seriously deplete the batteries in cold weather IMO.

Cheers,

Peter

PS — The Store Mode thread also has helpful info:

http://www.airforums.com/forums/f37/...de-175156.html