• Click here to access some of the presentations made during the 2022 National Rally

Minimizing current draw when on battery

Creek Jenkins

Creek Jenkins

Well-known member
I'm trying to make my batteries last as long as possible when boondocking. I have two RV type lead acid batteries and we camp about 5-6 months of the year but only boondock about 20-25 days, most of which are in the colder months so we run the furnace at night.

I shut off the TPMS booster, shut off the TV signal booster, turn the basement and front compartment lights to off, turn the door light on the fridge off but there are some loads I can't finger out how to turn off. I need to get a shunt so I can better see what is going on.

The thermostats bother me - the displays are not powered thru the AC unit, so shutting off the AC breaker does not turn them off. I realize I have to leave the center thermostat powered up so we can run the furnace, but so far the only way to shut off the thermostat display is to pull the fuse for the kitchen 12v power which I need for the fridge I think. Might have to dig into the back of the fuse panel and find the wires to the front and back thermostats and put them on a switch.

The other thing is the *@$%!*< radio over the fireplace. The ding dang damn display is always on and we never use the useless piece of kak - I have spent too much time trying to get the TV speakers to play over it and finally gave up. I heard even if you can get it to work the sound quality is schlecht. So I am going to endeavor to persevere to remove the fireplace drawer and see if I can disconnect power or perhaps put a shut off switch in. Maybe someday I will get a replacement radio and better speakers.

I know the thermostat display and the radio display do not pull a lot of power but every little bit might help. I imagine the kitchen fan and bathroom fan also pull some constant power with the rain detector sensor thingy always on even with the lid closed?

Any other ideas on what I could disconnect or put on a switch?

cheers,

Creek
 
Oregon_Camper

Oregon_Camper

Forum Admin
Staff member
Guessing you have a 12v refrigerator...right? That will pull about 4-5 amps an hour (when running). On average I'd say the frig is pulling 80-90 amp hours per day. That is a LOT for AGM/FLD battery bank, as you can only use 50% of their stated amp hours.

Side note...I did a video on this 6 years ago, but the data is the same, but prices for Lithium (not battle born) have fallen through the floor. Video link here...grab your favorite beverage, as I ramble on for close to 19 mins. LOL

Hunting down the other draws isn't worth your time...min amp (12v) pull from stuff like the thermostat and radio.
 
L

Lantley

Well-known member
12 volt fridge is not ideal for boondocking from the start. Lithium batteries are a game changer when boondocking with 12 volt fridge
 
Creek Jenkins

Creek Jenkins

Well-known member
I should explain a bit more, we have the standard 320 watt solar thingy and I have disconnected from shore power at home and let the solar run the fridge by itself, which works okay. When we dry camped before, the batteries were okay running the fridge and furnace in temps in the 40s. But then I had to get the dang CPAP machine and that causes the fridge to quit about 5 am if we use the furnace as well. I just need a couple watts to get me to 6 or 6:30 am so I can start the yenerator. I need to get one with remote start. Did I mention I hate the radio? With the shorter and warmer nights now I might be okay, we are headed to the mountains for a coupla weeks and night time temps should be high 40's low 50's so prob won't need the furnace much if at all. Also, I hate the radio.

cheers,
Turkey Creek Jack Jenkins
 
Oregon_Camper

Oregon_Camper

Forum Admin
Staff member
Ok..it worked before, but not with CPAP...got it :)

I would recommend a portable power station (like this one) and use it ONLY for the CPAP at night. Then recharge it during the day on generator power. The bonus with doing this vs adding more battery to the RV is you can use it at home as well, if you ever have a power outage.

Or...ditch your current battey lead acid battery bank and replace with the same amp hours but use Lithium batteries. Lithium batteries will allow you to use 100% of their power vs lead acid only allowing 50% discharge.
 
JWalker

JWalker

Well-known member
When I installed our lithium/inverter set up, we did a trial night running just off battery. Watching the increase of amp draw every time we turned on an appliance, lights, fridge, etc. We also wanted to run my wife’s CPAP machine as well. I was rather surprised on the amperage draw with the CPAP. Her CPAP machine has a heating element which creates the warm moist air she breathes. If I remember correctly. I believe it was 4-6 amps of draw.
 
S

stanburnb

Active member
1. Install shunt
2. Evaluate what you exact usage is.
3. If necessary change to lithium batteries

We mostly boondock and set up our rig for it. 909 ah of lithium batteries, 2200 watts of solar and Victron MultiPlus II inverter that I wired to power the entire trailer. Never worry about power. Yesterday ran the a/c for 5 hours and am 90% charged this morning.
 
You must log in or register to reply here.
Top