Quickly dead batteries

[PKRandy]

Hello, I have a 2011 Greystone 33QS with 2-27 series deep cycle Interstate batteries and they are new. Ever since I bought this unit new when I go dry camping my batteries go dead after 1.5-2 days even with very minimum use of 12 volt power items. The dealer has checked everything 2-3 times. We have checked every item one at a time for thier AMP draw and every item is in specs. I don't use much on lights because I put in my own individual LED lights with thier own batteries. My 2 batteries have been checked twice and there is nothing wrong with them. Hydrometer reading is level at 1.4 across all cells. I have load tested them and there is no problem. I am starting with 200 total AMP with both batteries at full charge and nothing I use even adds up to that many AMPs but they go dead in 1.5-2 days and that is without using the furnace witch has the greatest draw. I use my generator when I open my slides and put down my landing gear. I use a 10 AMP battery charger when I use my generator for about 4 hours a day and still the batteries go dead during the night hours. No one has an answer, the dealer or the factory. I am tech. savy and have tested every possiblity. Does anyone have a clue to what is causing this? When plugged into 120 volt there is never a problem with the converter handleing all the 12 volt items and it does keep the batteries at full charge. At witts end about this problem.
Randy

 

[jimtoo]

Hi Randy,

Welcome to the Heartland Owners Forum and family. We have a great bunch of people here with lots of information and all willing to share their knowledge.

I would think you need to put a amp meter between the positive cable and pos. battery terminal to see what the total amperage is your actually pulling from the batteries. Everything may check within specs, but they all add up. Then start disconnecting things to find out where the current draw is going. With all the parasitic loads now days, it would not take long to pull a battery down. Almost everything that is 12v will have a parasitic load, your NOAA radio, DVD player, stereo, Propane leak detector...

I'm sure some others will have more information also,,, probably better than mine.

Jim M

 

[evolvingpowercat]

Some thoughts...

1. My Dometic 3-way fridge draws 15 Amp DC when in 12 Volt mode, 0.5 Amp DC in 110 V or LP Gas Modes. Could your fridge be in 12 volt mode? This could happen if fridge is in auto mode and your LP Gas valve is off there is one that is dedicated just to the fridge in the gas line that feeds the fridge. Or if the fridge has LP gas but the flame won't light or stay lit causing its control board to fall back to 12 V mode when no 110 V is present.

2. Check your break away switch. Doubt this is the cause, but if the breakaway switch is activated, it puts 12 VDC from your 12 volt line tied to the RV batteries to the electric brakes.

 

[Rickhansen]

Aside from every load you turn on, there are quite a few "parasitic" 12vdc loads in your RV.
1. CO Monitor
2. Water Heater Circuit Board
3. Furnace Circuit Board
4. Refrigerator Circuit Board and inside light, plus the Condenser cooling fans.

I'm guessing these might total 2-5 amps continuous load. If you split the difference as 4 amps and look at it over 2 days, that's 192 Amp-Hours. The 200 amp battery rating is probably CCA, or Cold Cranking Amps, which has nothing to do with their capacity to sustain a load over time.

Here's a chart on interstate batteries: http://www.interstatebatteries.com/cs_estore/content/product_info/marine_f.asp

They list one group 27 as able to supply 5 amps for 17 hours. (not sure which battery you have) multiplied by 2 is 34 hours. Keep in mind that is probably with brand new, ideally charged batteries, perfectly matched for paralleling, yada-yada-yada.

I think your expectations are probably a stretch for these batteries to handle, and your charger is too light to recharge in 4 hours.

 

[pegmikef]

I use two six volt Trojan 105 batteries when I dry camp and run a fan all night long and have plenty of power in the morning. I run one of my generators for about three hours to charge them (using the TT's system) and my wife can do her thing with her hair accessories. I know that two Trojan six volts have a lot more amperage then two twelve volt batteris in parallel.

 

[evolvingpowercat]

I am going to put a 10 Amp Harbor Freight DC Amp Meter across my battery cutoff switch tomorrow morning and try to understand the various 12 volt parasitic draws by pulling 12 volt fuses, and will post the learnings tomorrow.

I think in my Edge there are the typical parasitic drains,
the Jensen audio system,
Dometic 3 way refrigerator, in total off and on in LP mode
maybe the space heater control board if the thermostat does not totally kill power to the thing
maybe the water heater control board if the monitor panel switch does not totally kill power to the thing
smoke and CO gas detectors
maybe the tank monitor panel

Am I missing anything I should check ?

 

[brianharrison]

Reserve Capacity (RC) and AmpHour (Ah) ratings are not the same. Rule of thumb is Ah=RC/2. Link to one online discussion.

Two six volt in series give about 220 Ah (20hr rating, trojan T105). Two 12 volts in parallel is about 200 Ah (100 each for a good quality group 27).

Brian

 

[wdk450]

If your rig has a Progressive series 9200 converter, it is a better battery charger than most any you can buy. Your best bet on recharging is to plug your rig into your generator for 3-4 hours daily. Here is a link to the Progressive charging stages (look at the chart): http://www.progressivedyn.com/prod_details/charge_wizard.html

Good luck on finding the parasitic drains. I would guess some troubleshooting with a DC ammeter will be in order.

 

[evolvingpowercat]

I have two group 24 12 volt marine batteries in parallel in my Edge M21. Marine batteries are designed to deliver 80% of their stored energy without loss of capacity after recharge. Group 24 "Walmart" type marine batteries typically are rated 80 Amp-hours at the 20 hour rate, that is the battery is drained from 100% charged to 20% charge remaining over 20 hours when drained at a constant 4 amp rate. Marine batteries have thicker plates so they can tolerate the deep discharge recharge cycles. Battery life is greatly reduced if batteries are discharged below 20% remaining. Battery life is extended if batteries are not often discharged below 50%.

You can estimate how much charge is left in a 12 volt lead-acid battery if you know "C" the capacity in Amp-Hours and you know the discharge rate by reading the voltage. Here are some graphs that show what is what: http://www.scubaengineer.com/documents/lead_acid_battery_charging_graphs.pdf

 

[westxsrt10]

A 10 amp charger will not properly charge two Group 27 batteries in 4 hours...maybe in 12-14 hours or more. I'd use your built-in charger @ 55 amps or more for 6-8 hours.

 

[evolvingpowercat]

> A 10 amp charger will not properly charge two Group 27 batteries in 4 hours...maybe in 12-14 hours or more. I'd use your built-in charger @ 55 amps or more for 6-8 hours.

The amount of time it takes to charge depleted batteries will depend on if you have a PD 91XX series or PD 92XX series converter. The 91XX series charges at 13.6 VDC then eventually steps down to trickle charge after many hours. The 92XX series has a smart three stage charger with a 14.4 VDC "boost mode" that will get you from 20% to 90% charge faster, then it will step down to 13.6 to complete the charge, then drop to trickle with a "boost shot" feature that gives the batteries a "shot" of higher voltage occasionally to help extend the life of the batteries. The 92XX is spec'd out to charge from 20% to 90% in 4 hours. It looks like the 91XX would take more like 40 hours to do the same. It looks like the 92XX series goes back to at least 2009 vintage Heartlands.

The converter manuals are on the owners forum tools pages.

 

[evolvingpowercat]

Measurements from my 2011 Heartland Edge M21

With all switches on monitor panel off, refrigerator off, on shore power with batteries charged: The converter is drawing 23 watts AC.

With AC power disconnected, same trailer mode as above: 0.2 Amps of 12 VDC being drawn from the batteries. 0.04 Amps from refrigerator fuse, 0.16 amps from the fuse that feeds the Jensen, Propane Detector, and Ceiling (CO?) Detector.

Refrigerator 12V increases to 0.1 Amps when on and in LP mode. FYI my RV has a Dometic 3 way single door refrigerator, 8 cu ft I think.

LP only Furnace, LP only Hot Water heater, water pump, monitor panel draw zero when all are off, LP hot water heater draws up to 0.7 Amp DC with switch in on position. Assume this would drop down to something less eventually but I did not wait to find out.

Other notes: Each bayonet type 12 V bulb used for all interior lights in my Edge draw: Standard = 1.3 amp, LED = 0.1 amp (I have changed first bulb in all fixtures to LED, left the 2nd bulb OEM)

Conclusion: in storage mode if I don't disconnect the battery my Edge uses about 5 AH per day, so I would go from 100% to 20% in about 30 days. For me this entire science experiement was about finding out if I needed to relocate my battery cutoff switch to a more accessible location rather than right on top of one of the batteries, its a pain to take the battery box cover off and get it back on the way the two batteries are located on my Edge.

 

[PKRandy]

Thanks my fridge only has LP and Electric modes but I will get an amp meter and check things again.

Some thoughts...

1. My Dometic 3-way fridge draws 15 Amp DC when in 12 Volt mode, 0.5 Amp DC in 110 V or LP Gas Modes. Could your fridge be in 12 volt mode? This could happen if fridge is in auto mode and your LP Gas valve is off there is one that is dedicated just to the fridge in the gas line that feeds the fridge. Or if the fridge has LP gas but the flame won't light or stay lit causing its control board to fall back to 12 V mode when no 110 V is present.

2. Check your break away switch. Doubt this is the cause, but if the breakaway switch is activated, it puts 12 VDC from your 12 volt line tied to the RV batteries to the electric brakes.

 

[PKRandy]

Thanks for the info. I did have the dealer go over everything with me on an amp meter reading from each item. We turned on each item and wrote down each item. I did get something about my batteries from someone on the Interstate web site that shed a good light on things. I guess I am exspecting to much from my batteries. Randy

 

[PKRandy]

Thanks for the information on the converters. I run both the converter and the 10 AMP charger at the same time when running my generator. I was told that the converter only usually gives out 2-AMP but it is good to know it gives out more. So I guess my 2011 must have the 92 series converter. I was told I was expecting to much out of my batteries and after looking at the Spec. from Interstate that seems to be the case. Randy

 

[PKRandy]

I checked the draw on my fantastic fans and also bulbs from the lights. If they combine a draw of 4-5 AMP continuouse draw that will kill the battery life in 17 hours for one and 34 hours for two batteries that I have. Gas valves draw AMPs also and I guess there is one for each LP item but don't know if that is always or when they just cycle on. The furnace draws the most but I only run mine a few minutes in the morning to take the chill off. They draw 4.5-6 AMP when running & lighting with the DSI. Thanks Randy

 

[piet10]

I have a 2011 Greystone 29MK with the same two batteries, and experienced the same issues as you. I thought the batteries were defective the same as you, but they are OK. The information on this thread has been very interesting.

One thing I noticed is the antenna booster has a switch to turn it off (was hidden below the TV) which I don't need while on battery. Also, the entertainment center is always backlit, so I will be putting an on-off switch to kill that when not in use.

Al

 

[PKRandy]

I called Heartland on my converter and it doesn't have neither the 91XX or the 92XX series. It has a off brand from Chain USA called a WF9865 that is 65 amps and I don't think it has the 3 stage step down fast battery charge sytem in it. I could not get a return call from Cahin USA's tech department. I guess if I ever had to replace it I would reseach and get the best one going. I saw something in Trialer Life Magazine that mentioned a good one and maybe it was the 92XX series that you are talking about but I have to find the article again and the month it was listed in the Magazine. Thanks again on the info. Randy

 

[TravelTiger]

We have the sane converter in our ElkRidge.

Here's what I found:

9800 Series Converter/Chargers are the versatile, advanced power source solutions. Output ratings of 35, 45, 55, 65, and 75 amps are available. Clean, reliable DC Power is ideal for powering electronics and appliances. The 9800 Series provides clean power even without filtering from a battery.
Quiet operation is assured as the cooling fan runs only when needed. The unit can be installed under your bed and never disturb your sleep. Another advantage is FCC Class B approval for every 9800 Series model, which means the converters do not cause interference with televisions, radios, and other signals.
Automatic three-stage charging maintains the life of your battery with output voltages of 13.2 VDC "sleep" mode, 13.6 VDC nominal charge, and a 14.4 VDC " boost " charge. 9800 Series also tolerate high input voltages without damage to internal components. Electronic current limiting automatically shuts down power during overload or short circuit conditions. 2 year warranty.

 

[Rickhansen]

Thanks for the information on the converters. I run both the converter and the 10 AMP charger at the same time when running my generator. I was told that the converter only usually gives out 2-AMP but it is good to know it gives out more. So I guess my 2011 must have the 92 series converter. I was told I was expecting to much out of my batteries and after looking at the Spec. from Interstate that seems to be the case. Randy

I don't think I would parallel the charger and the convertor. Both of these devices monitor the battery string for voltage and adjust their charge rates based on that. I believe the second voltage source could confuse the other system.