Dramatic battery power voltage drop while boondocking

[getaway432]

Just got our new Seneca 37k 2024, used on two trips now. while traveling and sleeping overnight on the road (no shore power) the house batteries only last about an hour. you can literally watch the voltage drop while looking at the control panel. it will drop from 13.4v to 10.9 within 50 minutes. Dealer checked it says everything is okay but there is no way it's okay. We will have water heater set to gas and use very minimal for lights no tv no heater. the refrigerator will be cold already after 3 hours on the road so it's not trying to cool form warm. Charging appears to be fine so no issues there.

We had previous RV and it would go about 6 hours before needing to charge it also had the residential fridge as well and 4 batteries.

Has anyone else had this issue with such a quick discharge?

 

[RogerR-JAY]

If you bought it new then there is hope that the most likely dead batteries are still under warranty.
In any case I would suggest you explore lithium batteries as they have several advantages.. Much lighter in weight, more compact, never need water and if you run them down to zero it does no damage.
If the fridge is a 12 volt it may be a big user even if it starts cold. The batteries sound like they were allowed to go dead in the past and have only a tiny charge capability.
I would charge them up with a shore power charger with no load until full and then see how they behave. That sharp drop off probably means dead.

 

[Rustynuts]

Yeah, that’s not right, one or more of the batteries is probably bad and pulling the rest down. You are under warranty, I would tell them to replace them under warranty. Better yet, if they will apply the cost, upgrade to Lithium.

 

[getaway432]

Thank you.

when I charge them up and put no load on the batteries after disconnecting the shore power should I see a drop on the battery voltage with no load over a short amount of time?

I will definitely push for battery replacement. Lithium would be nice but ouch expensive.

 

[Rustynuts]

13.4-13.6 is what you will see while being charged or a charger still on the batteries. When you disconnect the charge to it, with no load, they should normally drop to 12.7-12.8 in a resting state. If they drop rapidly with no load on them, it’s a good sign one or all of the batteries are bad. A simple Load Test of each individual battery should show any issues.

 

[getaway432]

Thank you

 

[RogerR-JAY]

Lithium batteries have dropped a lot and you can't directly compare. For example, a lead acid wet battery rated at 100 amps really has 50 or so amps available before the voltage drops and damage starts to occur. A lithium battery rated at 100 amps should actually give almost 100 amps and will not be adversely affected by discharging to near zero. Additionally, most lead batteries lose several percent of there total capacity every year.

 

[Kevin and Nanci]

If your batteries are dropping to 10.5 volts you likely have a bad cell (or battery) or you have a heavy load drawing them down. You didn’t mention if the fridge was on propane, 12v or 120v. Most auto parts stores will perform a battery load test for free. If they dropped below 10v has likely damaged a cell and needs to be replaced.

 

[videoarizona]

Agreed... Probably a dead cell. But, you should also check to see what your parasitic draw is with everything turned off. You may have a device that's still drawing power. Control boards for fridges and other appliances, plus the gas detectors all draw a small amount of power...all the time. Always a good idea on a "new to you" RV to establish a baseline on all things... Electrical usage is one. Good luck!

 

[Retired mountain folk]

Just got our new Seneca 37k 2024, used on two trips now. while traveling and sleeping overnight on the road (no shore power) the house batteries only last about an hour. you can literally watch the voltage drop while looking at the control panel. it will drop from 13.4v to 10.9 within 50 minutes. Dealer checked it says everything is okay but there is no way it's okay. We will have water heater set to gas and use very minimal for lights no tv no heater. the refrigerator will be cold already after 3 hours on the road so it's not trying to cool form warm. Charging appears to be fine so no issues there.

We had previous RV and it would go about 6 hours before needing to charge it also had the residential fridge as well and 4 batteries.

Has anyone else had this issue with such a quick discharge?

You can’t imagine the number of campers we speak with complaining about their batteries going dead after an hour. some have as many as six batteries, still goes dead. and All because of the refrigerator I’d never own a coach with a battery refrigerator. Electric/propane a must. 60+ years of experience with them. Good luck.

 

[Dragonheart]

Just picked up a used 2021 Seneca Prestige 37K with a very robust solar setup all Victron and Battleborn equipment. I had a 1300 ah draw not hooked to shore power. I had the DW watch the panel while I flipped breakers one at a time. Found the culprit real quick this way. Just a thought on something to try.

 

[Anyroad]

Thank you.

when I charge them up and put no load on the batteries after disconnecting the shore power should I see a drop on the battery voltage with no load over a short amount of time?

I will definitely push for battery replacement. Lithium would be nice but ouch expensive.

Lots of advantages swapping to lithium especially if you like to boondock. The initial out lay is more but prices have come way down and there are so many advantages. Lead acid just can't compare on any level.

 

[Lauren8363]

Thank you.

when I charge them up and put no load on the batteries after disconnecting the shore power should I see a drop on the battery voltage with no load over a short amount of time?

I will definitely push for battery replacement. Lithium would be nice but ouch expensive.

I really recommend looking into Lithium. May be expensive but in the long run it ends up quire a bit cheaper. Unless you destroy them by mis-use, the Lithium batteries will likely will be the last batteries you need to buy for this unit.

 

[JimD]

Just picked up a used 2021 Seneca Prestige 37K with a very robust solar setup all Victron and Battleborn equipment. I had a 1300 ah draw not hooked to shore power. I had the DW watch the panel while I flipped breakers one at a time. Found the culprit real quick this way. Just a thought on something to try.

Flipping the breakers when there is no 120 volt power will not do anything as the breakers are for 120 volt items. Removing fuses would be the test.

 

[Rustynuts]

That and a 1300 amp (1300ah for one hour) draw is HUGE

 

[440scout]

Put a clamp on meter around the positive battery cable, set it to DC amps then pull one fuse at a time to see what is pulling your battery down so quickly. You'll know in 5 minutes.

 

[Utrzrdog]

Not saying that Lithuim is not the way to go but I am on my 4th year with the 4 AGM batteries that came with the coach and have a residential fridge. I can boondock without a problem and the generator will only run 1-2 times a day to keep the batteries charged. I have the generator set to autostart at 12.2 volts and it will typically kick on in the AM after the furnace runs a bit for the night and then again later in the afternoon.

 

[RVermont]

Just picked up a used 2021 Seneca Prestige 37K with a very robust solar setup all Victron and Battleborn equipment. I had a 1300 ah draw not hooked to shore power. I had the DW watch the panel while I flipped breakers one at a time. Found the culprit real quick this way. Just a thought on something to try.

1300 amp hours in what time frame? 1300 amp is 16000 watts! Time is everything if that is an hour it would be very bad, but if that is 12 hours that is something completely different, still a lot but at least the system might be able to handle it.

 

[RVermont]

Flipping the breakers when there is no 120 volt power will not do anything as the breakers are for 120 volt items. Removing fuses would be the test.

If he has a full house victron system all the power will run through the inverter. I have a Victron unit and it will take up to 2400 watts or around 185 amps from the batteries but it will over load and shut off if I was to try to draw more than that. Since all power is run through the unit it does feed the breaker panels so a large 120vac draw will pull down the batteries.