Texas deep freeze

[Ranchertx]

Well, learning some lessons on my Momentum. We have no power so everything is coming from generators. I ran the Onan in the RV for a couple of days but last night, It was supposed to be only around 30 for a low.

I decided to give the onan a break and ran a cord to it from our genset hooked up to the house. I put a battery charger on one of the batteries and put it on 2 amp slow charge. I set the central heat on 55.

When I went to check it this morning the heat was out and the batteries were completely dead. So I hooked the RV powercord up to my genset via an extension cord and a 110v adapter plug.

The on board charger got the batteries charged back up today.

I know people boondock with these rigs. The two batteries wont run the heater for an extended time?
Or do you think I have a bad battery?

 

[GeoffnCheri]

Well, learning some lessons on my Momentum. We have no power so everything is coming from generators. I ran the Onan in the RV for a couple of days but last night, It was supposed to be only around 30 for a low.

I decided to give the onan a break and ran a cord to it from our genset hooked up to the house. I put a battery charger on one of the batteries and put it on 2 amp slow charge. I set the central heat on 55.

When I went to check it this morning the heat was out and the batteries were completely dead. So I hooked the RV powercord up to my genset via an extension cord and a 110v adapter plug.

The on board charger got the batteries charged back up today.

I know people boondock with these rigs. The two batteries wont run the heater for an extended time?
Or do you think I have a bad battery?

A furnace running all night will absolutely drain a battery.

 

[goodoz]

Well, learning some lessons on my Momentum. We have no power so everything is coming from generators. I ran the Onan in the RV for a couple of days but last night, It was supposed to be only around 30 for a low.

I decided to give the onan a break and ran a cord to it from our genset hooked up to the house. I put a battery charger on one of the batteries and put it on 2 amp slow charge. I set the central heat on 55.

When I went to check it this morning the heat was out and the batteries were completely dead. So I hooked the RV powercord up to my genset via an extension cord and a 110v adapter plug.

The on board charger got the batteries charged back up today.

I know people boondock with these rigs. The two batteries wont run the heater for an extended time?
Or do you think I have a bad battery?

What kind of batteries? Standard lead acid? AGM? Gel? Lithium? If they are anything "except" for Lithium, have they ever been deeply discharged before (below 50% ... 100% is about 12.7V charge...50% is about 12V charge...measured with a meter across both batteries)?

 

[BackCountry-MGRV]

I live in an extremely cold climate - sometimes during hunting season it is deep in the belows all night and only teens during the days. I have never had a problem running the heat off two lead acid batteries all night. They definitely need a day of Colorado sun to recharge on the solar panels for the next night or run the generator if it is snowing to recharge. I suspect there is another issue. Forget the 2 amp trickle charger. Use your generator or shore power to charge the batteries through the on board inverter.

 

[Chewwi]

Our GD owners manual indicates the furnace uses 12A. Setting the charger for only 2A results in a 10A deficit.

 

[RV Sailor]

What kind of batteries? Standard lead acid? AGM? Gel? Lithium? If they are anything "except" for Lithium, have they ever been deeply discharged before (below 50% ... 100% is about 12.7V charge...50% is about 12V charge...measured with a meter across both batteries)?

Not so fast. The all encompassing statement is incorrect.

Oasis Fireside carbon foam AGM can be drawn down like lithium with no tremendous penalty to life cycles like a regular lead acid has. While what you say applies to many types of batteries using sweeping statements to describe all of them is absolutely incorrect. Many boaters have been using this type of battery for years. Not sure why it hasn’t caught on in the RV market. Probably because of the infatuation with lithium.

https://oceanplanetenergy.com/advanced-energy-storage-systems/firefly-energys-oasis-group-31/

 

[goodoz]

Not so fast. The all encompassing statement is incorrect.

Oasis Fireside carbon foam AGM can be drawn down like lithium with no tremendous penalty to life cycles like a regular lead acid has. While what you say applies to many types of batteries using sweeping statements to describe all of them is absolutely incorrect. Many boaters have been using this type of battery for years. Not sure why it hasn’t caught on in the RV market. Probably because of the infatuation with lithium.

https://oceanplanetenergy.com/advanced-energy-storage-systems/firefly-energys-oasis-group-31/

Sheesh...it was posed as a question, not a declarative statement. How do those fancy AGMS fare when you completely deplete them (as the OP did with his)? IMO (there, I qualified it), most folks are rolling with the single battery the dealer provided, that same battery with one they added from Wally World and/or their 3rd or 4th set of Wally World lead acid batts because they keep killing them by over discharge (that's about where I was).

 

[Scramjet]

I know people boondock with these rigs. The two batteries wont run the heater for an extended time?
Or do you think I have a bad battery?

Texas Rancher,

The owners manual for my Reflection 303 says 12 amps for the furnace (about 144 watts). My actual measured power consumption is about half of that at 75 watts. If my furnace runs 1/3 of the time it would consume 300 watt-hours in 12 hours.

Your typical group 27 battery has about 85 amp/hours or just over 1,000 watt-hours capacity. If you have 2 batteries then double that capacity. If nothing else was on you should have been fine for overnight. BTW, forget that 2 amp trickle charger, that will not even begin to recharge your batteries.

From what you have described you either have a bad battery, started from a charge deficit or had other loads running.

Brian

 

[Ranchertx]

Our GD owners manual indicates the furnace uses 12A. Setting the charger for only 2A results in a 10A deficit.

Makes sense. Over the course of 12-14 hrs that is 120-140 amp hour.

My batteries are standard Interstate deep cycle.

 

[Ranchertx]

The only other thing going was the tank heaters. I wonder what those draw?

 

[Ranchertx]

I read an rv tank heater draws between 4 and 11 amps. The RV has 3 of them so thats another 15-30 amps per hour. I guess that is why the battery’s were dead.

 

[RV Sailor]

Sheesh...it was posed as a question, not a declarative statement. How do those fancy AGMS fare when you completely deplete them (as the OP did with his)? IMO (there, I qualified it), most folks are rolling with the single battery the dealer provided, that same battery with one they added from Wally World and/or their 3rd or 4th set of Wally World lead acid batts because they keep killing them by over discharge (that's about where I was).

I agree with you about most people’s use of batteries that are supplied by dealers. In fact I think most really don’t understand how their electrical components relate to their power until of course it doesn’t work. And again I agree they keep killing them by over discharge.

I think people learn on here by being exposed to others ways of overcoming , new projects for improvement, and new technologies. That’s why I mentioned the Firefly AGM. It’s a lead based AGM with a lot of properties that people buy lithium’s for. Some advantages even in safety and cost.

In the OP case it may not have deadened like his wet cell.

As far as depleting to zero, it’s not good for any battery. I’ve know a few Fireflies take down past 20% and they recovered.
Unlike other AGM they can be left in a depleted state without penalty where that is death for most lead based batteries.

My post was to give others a look at another option other than wet, standard AGM , and lithium options. These batteries are used extensively by world cruisers especially and are quite common on the west coast of the US as options. Not sure why they have not caught on.

I have no affiliation with Oasis....just a very satisfied customer.

 

[Second Chance]

Our GD owners manual indicates the furnace uses 12A. Setting the charger for only 2A results in a 10A deficit.

That's a little over-simplified. The furnace doesn't usually run 100% of the time. If it did, your calculations would be correct. The furnace cycles, using its 12 amps intermittently. The batteries function as an energy reservoir that can be at, slightly above, or below "pool level" (using the reservoir metaphor). The charger needs to provide enough energy to bring the batteries back up to full charge level after the furnace fan motor has drawn them down. Unless the furnace is running 100% of the time, this will not require 12 amps of charge current.

Rob

 

[wjpatter]

I read an rv tank heater draws between 4 and 11 amps. The RV has 3 of them so thats another 15-30 amps per hour. I guess that is why the battery’s were dead.

Those maybe your bad actor. I measured the current draw from the battery with heat and blower running and got 7.2 amp (90-100watts) and has been pointed out only runs from time to time. Those tank heater are probable running 24/7.

 

[Ranchertx]

I agree with you about most people’s use of batteries that are supplied by dealers. In fact I think most really don’t understand how their electrical components relate to their power until of course it doesn’t work. And again I agree they keep killing them by over discharge.

I think people learn on here by being exposed to others ways of overcoming , new projects for improvement, and new technologies. That’s why I mentioned the Firefly AGM. It’s a lead based AGM with a lot of properties that people buy lithium’s for. Some advantages even in safety and cost.

In the OP case it may not have deadened like his wet cell.

As far as depleting to zero, it’s not good for any battery. I’ve know a few Fireflies take down past 20% and they recovered.
Unlike other AGM they can be left in a depleted state without penalty where that is death for most lead based batteries.

My post was to give others a look at another option other than wet, standard AGM , and lithium options. These batteries are used extensively by world cruisers especially and are quite common on the west coast of the US as options. Not sure why they have not caught on.

I have no affiliation with Oasis....just a very satisfied customer.

The system is showing 13.4 volts on the monitor panel now with Tank heaters and Central heat on, so, I hope the batteries have survived.

My advice to others is, do not boondock in cold weather with heat and tank heaters going.

 

[goodoz]

Sheesh...it was posed as a question, not a declarative statement. How do those fancy AGMS fare when you completely deplete them (as the OP did with his)? IMO (there, I qualified it), most folks are rolling with the single battery the dealer provided, that same battery with one they added from Wally World and/or their 3rd or 4th set of Wally World lead acid batts because they keep killing them by over discharge (that's about where I was).

That said, I took a closer look tonight and these Firefly batts look pretty good...I wasn't aware of them and learned something. Similar performance to LiFePO4 (including complete discharge). Why haven't they taken off in the RV world? My guess would be their weight...they are heavy and lighter is better for tow vehicle payload limitations...probably not so much of a concern on a bobbing boat...they may help you plane out ? Forum discussions are cool!

 

[Keebler]

Oasis Fireside carbon foam AGM can be drawn down like lithium with no tremendous penalty to life cycles like a regular lead acid has. While what you say applies to many types of batteries using sweeping statements to describe all of them is absolutely incorrect. Many boaters have been using this type of battery for years. Not sure why it hasn’t caught on in the RV market. Probably because of the infatuation with lithium.

https://oceanplanetenergy.com/advanced-energy-storage-systems/firefly-energys-oasis-group-31/

Very interested in the carbon foam battery. Do these require any specialized charging equipment?

 

[Chewwi]

That's a little over-simplified. The furnace doesn't usually run 100% of the time. If it did, your calculations would be correct. The furnace cycles, using its 12 amps intermittently. The batteries function as an energy reservoir that can be at, slightly above, or below "pool level" (using the reservoir metaphor). The charger needs to provide enough energy to bring the batteries back up to full charge level after the furnace fan motor has drawn them down. Unless the furnace is running 100% of the time, this will not require 12 amps of charge current.

Rob

You are correct. My post should have ended with “. . . when the furnace is running.” The point being that 2A charging wasn’t likely to keep the battery charged as the OP found out the next morning.

 

[papermakermd]

I'm in the Rio Grande Valley and just survived the freeze here in Texas. I must have one hell of a good battery. It got down to 26 Sat. night with a wind chill of 10. My battery lasted all night no problem. I charged it back to full charge off a generator and a 4 amp Battery Tender and used it all night the next night in the same temperature minus the wind. No problem.