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DennyO 08-17-2020 06:13 PM

I'm So New, I Don't Know What I Don't Know!
Like I said, I'm a newbie and want to learn. I have had my 2020 Interstate GT for 6 weeks and have been to 3 RV parks with full hookups and one winery parking lot. That was our first boondocking experience. My concern is about battery life; mainly for keeping my food and drink at proper temperature. Even thought we have all the fancy stuff, i.e., microwave and TV, I know how to conserve energy. Basic question - does the inverter need to be on all the time, even when I am driving?
How much energy does the inverter draw?
How do I know when my batteries are dangerously low?
Like I said, I don't know what I don't know, but want to learn.
Thanks in advance.

Rig Rat 08-17-2020 06:26 PM

No, your inverter does not need to be on. If you were Boondocking And you wanted to watch TV then you would turn it on.
Otherwise while Boondocking you would run your generator to use your microwave or air conditioner
You do not want to draw your batteries down more than 50% which is around 12.2 V.

GetawA-S 08-17-2020 06:33 PM

You’ll go far if you:
Don’t hit anything, and
read the manual.
Battery capacity varies, based on history (of abuse). Look at how many amp hours yours are rated for. Get a feel for how much load the trailer accessories draw. Allow for charging from your solar or generator. Do the math - amps out, amps in.
I won’t go on, because frankly there have been so many similar threads it’s starting to clog the forum. Browse around and hone your “search “ skills.

DennyO 08-17-2020 10:36 PM


DennyO 08-17-2020 10:38 PM

Thanks for your suggestions

pmclemore 08-18-2020 07:57 AM

If you want to learn your capacity for boondocking (or dry camping) try setting up your rig at home and camp there. Or just don't hook up when you're at a full-hookup site and test your camping style.


John & Roberta 08-18-2020 10:32 AM

You don't know squat—
(Roberta and I are still in the squat position . . . have fun!)

lrlevine117 08-18-2020 10:34 AM

read the manual
I am also a newbee with an Airstream Interstate 2017. The manual does not answer the electrical questions. It mainly points you to the equipment brochures and they are hard to understand. This is not to say that over a period of time, things will become easier to understand but as a newbee, everything is confusing. Especially the electrical system and boondocking. Regardless of how many threads there are on this subject, everyone can use the help of those more experienced. Reading the manual may help but it does not answer the questions.

An example is the nova kool refrigerator and freezers. I just was told that when on 12 volt, they will not cool down, they will only maintain a temperature. They need 120 volt to cool down. Knowing how long you can be off the grid with these units can be very confusing.

I am also told the inverter uses a lot of amps. Someone mentioned that you should turn it off. How do you turn it off? I missed that info in the manual.

I also hear that you should not run your batteries dead. Before I started digging into things, dead meant to me zero V. Now I find out that dead means around 10 volts. How do you know when you are approaching that level? I don't see any indicator that alerts you.

So these are just some of the confusing things that we rely on other people's knowledge to help us. Would also help if Airstream could provide a better manual.


Pahaska 08-18-2020 11:56 AM


Originally Posted by lrlevine117 (Post 2399105)
An example is the nova kool refrigerator and freezers. I just was told that when on 12 volt, they will not cool down, they will only maintain a temperature. They need 120 volt to cool down. Knowing how long you can be off the grid with these units can be very confusing.

I am also told the inverter uses a lot of amps. Someone mentioned that you should turn it off. How do you turn it off? I missed that info in the manual.

Whoever told you that was confusing the compressor refrigerators in the Interstates with the 3-way refrigerators used in some trailers. In those, the 12v mode just holds temperature when on the road. In the Interstate, the refrigerators are 12v always. 120 volts is simply reduced to 12v inside the refrigerator when you have 120v available. That just reduces the load on the Magnum converter/charger.

The inverter doesn't use a lot of power idling. If there is nothing drawing power from the two TV outlets and the DVD player outlet, it merely polls the bus to see whether power is needed. That is a fairly small draw and only matters if you are boondocking and trying to stretch the batteries. You turn it on and off with the on/off button on the Magnum display.

Toasterlife 08-18-2020 12:57 PM

Every trailer is different - they (almost) have personalities but over time you will get your know yours and learn how to adapt or what needs to be changed.

Here are a few tips from folk with a 10 year old rig who mostly boondock.

Our "Toaster" is 2 different rigs, one with power has a microwave, surround sound, AC and a furnace, long showers with hooked up water, etc.

The other "Toaster" when boondocking has none of the above.

One handy tool is a little battery operated fan that goes in your fridge - about $10 on amazon, circulating air helps keep things cool. A fridge thermometer is handy too, I would say it is a must. In hot weather we "help" the fridge by putting block ice - or a bag of ice in a plastic tub in the fridge - we drink the icemelt.

We cary a generator but rarely use it preferring to use our solar panel which has a long lead so we can park in the shade and move the panel as the sun moves.

Awning plus a fan, can really enhance your comfort without the need for noisy AC. If it is truly too hot for awnings and a fan consider if your really want to be camping there, or if you want to relocate to different location. We don't plan to camp in extreme temperatures. you can certainly get caught out by hot or cold extremes, but can often plan around it.

When boondocking don't count on your furnace unless you run the generator simultaneously. Warm socks, extra blankets and a hot water bottle are your friends. Bake a cake (with safely cracked windows) to get a little extra warmth and the the rig will smell great.

We use our luci lights on the inside when boondocking - abut $15 at REI, rechargeable solar and a lovely warm glow. Useful inside and out.

Keep the inverter off when not in use. Similarly with the water pump. Only turn it on when needed.

Everyone has a different reason to camp. We love to wake up in nature, so are willing to leave (some) of our comforts of home behind for the privilege.

Other people value the TV and AC and long showers - campers will self segregate to their preferred environment. Not better or worse just "horses for courses".

Over time you will find out what kind of a camper you are and adapt your behaviour and rig to your own needs.

lrlevine117 08-18-2020 01:24 PM

Just to be clear, are you saying that if I am disconnected from 30amp, and not using my generator, the Nova Kool units will cool down? Or just maintain their temperature? Thanks.

Photobum 08-18-2020 01:36 PM

May I suggest that you google a few businesses that you will be meeting soon I suspect.

AM Solar
Battle Born Batteries

Congratulations. The world you are about to enter is one with lots of good days.

Pahaska 08-18-2020 02:47 PM


Originally Posted by lrlevine117 (Post 2399179)
Just to be clear, are you saying that if I am disconnected from 30amp, and not using my generator, the Nova Kool units will cool down? Or just maintain their temperature? Thanks.

So long as your batteries are not depleted, the refrigerator will cool on 12v just as well as on 120v. 120v is simply internally converted to 12v. You can't tell the difference.

In all but the hottest summer, mine is almost cooled down in the time it takes to prepare the Airstream and drive the 10 miles home.

Passin Thru 08-18-2020 05:56 PM

I think the best answer to give you is to use this forum. There are some very knowledgeable people on this forum who have addressed just about every issue with our coaches. Use the search field at the top of this forum with your specific subject and I think you will find your answer.

Most importantly - enjoy!

toskeysam 08-18-2020 06:27 PM

Denny O just keep asking questions. We’ve all been newbies at one point.

Titus 08-23-2020 07:13 AM

While you can use the battery voltage to determine battery state of charge (SOC), the battery needs to have been sitting for several hours without any current in or out to get the correct voltage. This is not really practical when you are out boondocking and using the battery to run the refrigerator. I suggest getting a battery monitoring kit, and the upgraded Magnum remote. And you might as well get the Magnum temperature compensation while you are at it.

Unfortunately the lowest value the Magnum BMK and remote can be programmed for is 200AH of battery capacity, so you are off a bit with 2 Group 24 AGM batteries that have 160AH. Examples:
90% SOC for 200AH = 20Ah used = (160/20)/160=87.5% SOC for 2 Group 24 AGMs. 50% SOC for 160AH = 80AH used. (200-80)/200 = 60% SOC on the Magnum remote.
I upgraded to 200W solar and Blue Sky MPPT controller and am very conscientious (anal) about power usage. Lowest I have ever seem while using Titus is 68% SOC on the remote which is actually 60% SOC. Lifeline batteries should last 1500+ cycles with this maximum amount of discharge.

PS: The above is for my 2013 Interstate. You may have different batteries and/or Magnum setup.

DavidEM 08-23-2020 08:01 AM

Battery voltage is only a very approximate indication of state of charge (SOC) and can be wildly off. It is best when the batteries have been at rest with NO amperage draw for at least an hour. Drawing 10 amps will cause the voltage to temporarily drop by 0.2-0.4 volts but it will come back if you let them rest.

Given that weakness, if you plan to boondock for more than a day, then install a battery monitor. Renogy makes a fairly inexpensive one, but Victron and others make them. They measure real time amperage and integrate it against time to give you real amp hours used and amp hours added due to charging.

The DC fridge (and yes it cools as good on DC as on converted AC) draws a fair amount of current, probably 60 amp hours in 24hours. With just two Group 24 batteries and just a little more amp hours you will be down to 50% SOC in a day.

I understand that the Interstate has two battery storage positions near the rear wheels. They may be able to take larger batteries- check the net. If Group 31s will fit that will bring your total amphours up to 200 or 30% more than the G24s and 100 AH usable. But that still won't last two days typically.

Installing two lithium batteries such as Battle Borns will last two days as that will boost your usable AHs to 180. But you need to recharge them. Search the net for a "dongle" solution for your existing converter or change it out for a lithium specific one such as the Progressive Dynamics 9100AL series. A 45 amp converter can be run with as little as a Honda EU1000, but if you upgrade to the 80 amp 9180AL then you can recharge faster but it will take a EU2200.

And finally if you camp in a sunny spot, solar can also help your amp hour balance.


Mollysdad 08-23-2020 08:22 AM


Originally Posted by DennyO (Post 2398880)
Basic question - does the inverter need to be on all the time, even when I am driving?

I have never turned my inverter on!
Maybe I should experience a new and exciting feature!:blush:

Hawk-ination 08-25-2020 07:32 AM

DennyO, welcome to the group!

We’ve had our Interstate for a year now and we are still learning!
We bought from an individual who didn’t know much about the Interstate, so we learned by trial by fire. Asumed our solar would keep our batteries up and cooked our batteries by not plugging our AI in right off the bat. Found out things like not to run your AC off anything but 30 Amp RV service. Went through a nasty electrical storm on our maiden voyage and found out having a surge protector is neccessary.

We just went through a week without power due to a derecho and I learned a few more things on how to boondock, even though I thought I had enough knowledge to do it without thinking very hard. Found out it’s good to know certain things like how long your generator will run on a fill of propane. Wish I would have tried it without having it be neccessary, like you’ll hear people suggest.

I agree with the other posters, watch your voltage on your batteries. There’s a lot of what they call parisitic draw on your batteries even when you think everything is off. It will run your batteries down in a matter of time, a day, a few days, depending on your solar input, too. More than what you’d expect, in my opinion. Until you figure these things out or research them quite a bit, keep your batteries healthy and charged up by plugging your rig in as much as you can.

I found it confusing at first, having no instructions, on what works when on generator power, electric power, boondocking, when the inverter is needed as you asked, etc. I disagree on going to the manual somewhat. Read it, but it doesn’t explain especially well how these systems work together, in my opinion. If you have the chance, hook up with a couple memebers if you find specific questions or post them on the forum. There’s a lot of memebers who are really helpful and happy to walk you through things. I wish we would have started off with a tutorial with someone who knew what they were talking about. There’s a lot of little hints that can save you some issues down the road.

Wish you luck, and again, welcome to the club! Safe travels!

gator.bigfoot 08-26-2020 10:59 AM

Install a battery monitor. There are more variables than just the voltage. Voltage will vary depending on temperature. A battery monitor will tell you battery capacity (if programmed correctly) and let you know your usage. This I find is the most import thing. Knowing what you are using when. For instance if I run my roof fan at low speed I'm maybe drawing 0.5 amps. If I am running at high speed then perhaps 2+. So things like that are important so that you can calculate if you have enough capacity. It will also let you know how much you use and how much gets put back into the battery the next time you drive or if you have solar how much gets put back from the solar panels. It keeps a history of these things as well. If your going to use your batteries then a battery monitor is a must for every user. The 2 most popular ones out there are the Trimetric from Bogart Engineering and the Victron. But there are others.

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