Community Forums

honjackson · 02-18-2021, 10:18 PM

I know there was an older thread but I thought there might be some updated suggestions. In a couple weeks we're picking up a new, but last years model, (2020) Ventana. I suspect its been on the lot for a year. I know the dealer is going to say everything is "new" but our concern is the condition of the house batteries. Having been around several dealerships I noticed that none of these places keep the mh plugged in or the batteries up. Almost every time they have to plug it in for awhile or get the engine jumped to to show us the slides work. I have read that dropping these lead acid batteries to less than 50% can drastically reduce their life and I imagine running them all the way down can be fatal. I don't know what the dealer is going to say about the batt condition but is there any easy way for me to load test them before I take possession without buying a load tester device and then disconnecting each battery for testing? I have a volt meter but no way to put a load on them. There are 8 6 volt batteries as I understand it. Lithium is in the future but can't be done now. Sure, they may say there is a warranty but we live hundreds of miles from this dealer. Thank you for any suggestions. Bob Jackson, Fruitland, Idaho

RKins · 02-19-2021, 05:45 AM

You could buy a cheap hydrometer and test each battery after they have sat for a little while - tell the dealer that if they fail the test they must replace all batteries.
https://www.walmart.com/ip/Unbreakab...6381456e06f0f0

clawsonbob · 02-19-2021, 06:37 AM

Quote:

Originally Posted by RKins

You could buy a cheap hydrometer and test each battery after they have sat for a little while - tell the dealer that if they fail the test they must replace all batteries.
https://www.walmart.com/ip/Unbreakab...6381456e06f0f0

This ^^^^.

I bought a new “leftover” Jeep Sahara Wrangler last year that sat on Dealers lot For 10-11 months. I too questioned the status of the dual batteries and made concerns known in writing (for the record). Both required dealer replacement shortly after I took delivery.

Good luck and enjoy that nice rig !!

C.Martin · 02-19-2021, 07:24 AM

Taking a hydrometer reading is great for Flooded...but obviously not AGM. It will show a ballpark State of Charge. And by comparing each cell to one another you can tell if you should equalize.

True measure for Deep Cycle batteries normally would require a device. There are timed load devices, commonly used for Golf Cart service. And more expensive OEM testers that use Electronic Impedance Spectroscopy. These testers will actually quatitatively give you your existing 20hr aH capacity left on the battery.

The best way to load test your batteries is to set the AGS, unplug...and camp overnight using battery storage and inverter alone. If you can run a TV, fridge, reheat something in the microwave, use your 12v water pump to shower, recharge your laptop, etc...and wake up without the generator kicking on...you have storage. If your generator kicks in at 3am, chances are your 8 batteries aren't doing what they were designed to do.

There are plenty of lead acid graphs on Google that show state of charge vs voltage, many have stacked curves to represent the variances caused by loads. The loads will be defined by amps as a fraction of your total storage.

If you have 900aH...and plan to measure the voltage while drawing 9amps...that would require you to reference the C/100 curve. If you measured voltage while drawing 90A that would be the C/10 curve. If you have a clamp meter or install a BMK...you can measure your load. C/100 is a load which would take 100hrs to draw the battery down to 10.5v (zero state of charge). C/20 would be 20hr load...which is the standard for rating the batteries. C/10 is a 10 hr load. As you get to the higher loads...the aH lost are not on a 1:1 ratio...as battery impedance causes heat energy loss. A phenomenon refered to as peukert effect.

Going to all of this hassle isn't a lot of fun...but it would be a good idea to check annually. It's a good way to tell when your batteries have lost enough of their original capacity that it would be a good time to replace them.

In between tests...you can use resting voltages, specific gravity, or a simple counter like the ME-BMK or Victron SmartShunt500 to give you an easy to glance at figure.

Drawing batteries down is using a cycle. The deeper you discharge the quicker you chalk up cycles...which are basically battery lifespan. The bigger problem is how long they are left in a discharged state, when?, and how where they recharged. Shallow discharges that are not left to linger recover quickly when recharged. Do not require lengthy absorb cycles...and aren't in danger of freeze damage. Deeply discharged batteries, normally require higher amperage charges, more lengthy absorb cycles, and were potentially subject to freeze damage while at a low specific gravity. Specific gravity of electrolyte solution...like engine coolant...has an associated freeze point temperature. The closer to zero...the less cold tolerant the battery will be.

Set your AGS for 12.2v trigger voltage...unplug and go the night. If you have a startup just caused by a couple of outlets and a residential fridge ..your batteries should be replaced. I can run thru the night with other aplliances...and still be up around 80% SOC. 12.2v is approx. 50%. That would be where I would be replacing the batteries.

chs · 02-19-2021, 07:29 AM

Quote:

Originally Posted by honjackson

I know there was an older thread but I thought there might be some updated suggestions. In a couple weeks we're picking up a new, but last years model, (2020) Ventana. I suspect its been on the lot for a year. I know the dealer is going to say everything is "new" but our concern is the condition of the house batteries. Having been around several dealerships I noticed that none of these places keep the mh plugged in or the batteries up. Almost every time they have to plug it in for awhile or get the engine jumped to to show us the slides work. I have read that dropping these lead acid batteries to less than 50% can drastically reduce their life and I imagine running them all the way down can be fatal. I don't know what the dealer is going to say about the batt condition but is there any easy way for me to load test them before I take possession without buying a load tester device and then disconnecting each battery for testing? I have a volt meter but no way to put a load on them. There are 8 6 volt batteries as I understand it. Lithium is in the future but can't be done now. Sure, they may say there is a warranty but we live hundreds of miles from this dealer. Thank you for any suggestions. Bob Jackson, Fruitland, Idaho

I personally would insist on NEW batteries be installed before you buy it. Twice Mine failed with two different buys. RV units sit in the yard with NO charger / Maintainer on them, When you buy it, all they do is charge it back up again. Anyone that knows batteries. Once they go dead, you lost half their life (or more) The class C I own now, the batteries went dead 4 months of purchase.

Mark_K5LXP · 02-19-2021, 08:17 AM

Quote:

Originally Posted by honjackson

I have read that dropping these lead acid batteries to less than 50% can drastically reduce their life

Not really true. But what is true is if they're *left* at some state of discharge for any period of time which is an entirely plausible scenario in this case. Eight batteries isn't chump change no matter what kind they are, so I'd definitely want to know if they were any good.

Quote:

is there any easy way for me to load test them before I take possession without buying a load tester device and then disconnecting each battery for testing?

You wouldn't have to buy any special equipment, you can use existing house loads as long as you can measure actual load current. Testing each pair is nice but you can also test them as a set.

A capacity test would reveal a lot. Would involve a known complete charge cycle (including equalization if FLA) then a timed discharge test at a measured current. I would probably do two or three charge-discharge tests in succession, since if these really are new batteries and haven't been cycled much they may still exhibit a reduction in capacity even if they weren't neglected. From there you can decide if a replacement or prorated depreciation can be negotiated.

Quote:

I imagine running them all the way down can be fatal.

Depends on how far "down" is and for how long. Definitely not on the "good" list of things to happen though.

Quote:

I have a volt meter but no way to put a load on them.

Does this RV have an inverter? Plugging AC devices into that will allow you to dynamically create whatever load you need. An external inverter connected directly to the bank would be another way to create a suitable load.

Mark B.
Albuquerque, NM

hohenwald48 · 02-19-2021, 12:00 PM

Not sure what good it would do the load test the batteries. Do you think the dealer will replace them if you get a load test you don't like? I doubt it. It's best to just factor in a set of batteries into your purchase offer numbers then use them until they die and buy new ones.

Insisting on new (recent dated) batteries might work if the deal isn't done yet. Depends on how bad the dealer wants to move the unit I suppose.

AnotherMike · 02-19-2021, 12:20 PM

i'd insist on:

1) a professional pre-delivery inspection, and fixing everything on the gripe list that the inspector generates.

2) you watching the dealer guys unbox a set of brand new batteries and install them.

Mike

swaff54 · 02-19-2021, 12:21 PM

You should also be concerned about the chassis batteries.

Long story short, we purchased a new 2019 Ventana 4037 on October 15, 2019.

In June of 2020 I got a transmission code that turned out to be a low voltage issue. The chassis batteries were no longer holding a charge.

Spartan said that the batteries were put in the chassis in July 2018 and that the 1 year warranty on them was well expired.

I ended up paying for new chassis batteries. The good news is that Newmar stepped up and reimbursed me for the new batteries.

Edit to add

The house batteries have been fine.

"007" · 02-19-2021, 07:55 PM

Welcome to the forum and the ownership of a Newmar.
You have received some good advise on the batteries I will give you
this link with more info for your new coach and advise the dealer have coach plugged into at least 110 volts or running the Gen before moving the slides do not move slides with the battery systems only.
This link will explain slide systems and their operations and possible faults in operation.
Good luck on your PDI, enjoy the forum and coach and safe travels.

PetesMH · 02-21-2021, 01:57 PM

We bought our 2019 coach after it had sat on the lot for most of a year. Both flooded house batteries failed on our first trip. Rather spectacularly actually. Both the dealer and Interstate Batteries refused to replace them. I was on the road so I did it myself and called Newmar when we got home and they promptly reimbursed me for the full cost. The chassis battery failed a short time later and I just replaced it myself. You can try to insist on all new batteries before you take delivery and probably will be successful. Otherwise just keep an eye on them and be ready.

honjackson · 02-21-2021, 06:14 PM

Thank you all. Some ideas I had not thought of. There are some real knowledgeable folks on this site Bob Jackson

Suzuki.Bruce · 02-21-2021, 06:35 PM

I would insist the dealer write a special exception on the sales contract to replace the batteries if they fail within a year. I bought a MH that had been on the lot for an extended period and had to replace 2 of the 4 house batteries at about 6 months. Also, I would recommend putting some new battery caps that actually show the battery fluid level, without taking each cap off and looking inside. Many converters tend to overcharge. These battery caps are a great invention.