Electrical caravan electrical setup advice

[shmick]

Hi all,

So we ended up placing order for a Jayco Journey Outback (15.48-6). Yay.
So now I'm planning for the future as I have a 6 week trip planned (assuming virus is gone) very shortly after I take delivery. I want to be ready.

I have a 70Ah lithium battery in the boot of the Prado that runs my fridge.
It has been running off a VSR and alternator for a few years successfully, but I feel the lack of proper charging is affecting it (I top it up here and there with 240V Victron charger).
I am planning on putting an Enerdrive dcdc in the boot to charge the battery properly and with solar if needed.

I also bought an additional 100Ah lithium for the camper that I never built, then intending to put it in van to run the fridge and TV.
Now the caravan threw a spanner in the works as Jayco only allow the BMPRO J35D (lithium capable) BMS on the Adventurer and Silverline models.
Therefore I'm stuck with J35B which is AGM only and a spare 100Ah LiFePO4. What would you do?
(PS. I intend to use the standard AGM in the van for lighting and charging devices and use the 100Ah lithium for TV and fridge duties in the van).

1. Easiest is to keep lithium in my car and just plonk another AGM in the van bringing it up to 250Amps. Cheapest option. Easiest option. Heaviest option. Will 250Ah AGM deal running fridge, TV, lighting and charging phones for 2-3 days (Van has 160W solar too).

2. Put the 100Ah lithium in the van and just run cables from the boot battery to simultaneously charge the van lithium leaving the stock AGM system alone.

3. Get 2 Enerdrive units, one for the car and one for the van. Most expensive option. Well apart from purchasing the J35D standalone for $1000.

4. Do I just bypass the whole J35B and use an enerdrive instead with a fuse box for all the plugs. And also would need AC charger. Hard to justify.

I dont want to totally dismantle the standard system as it is already wired up and monitors everything conveniently. I'm also trying to avoid weight (more AGM) as they have a poor payload as it is.

What are your thoughts.
Thank you
(All this is because I read everywhere that gas does not cool anywhere as well as electric.)

 

[Drover]

Fridge does not operate well on 12v and will kill a battery in an hour or so, gas is great for a 3 way, if your using your van for 6 mths a year then go the lithium option if not then go AGM and save your money.
Your van 12v system runs water pump, radio, lights, possibly TV, it doesnt operate the fridge, the 12v on fridge only used when hooked up to tug with engine running. Of course this if for a 3 way.

 

[shmick]

Well that changes things. I wasn't aware of that.
Van will be used less than 3 months, not by choice.
Does Jayco wire them up like that or are they generally not suited to 12V?
Suppose no issue on powered sites, we just like to get away at times.

 

[Drover]

You basically have 2 types of fridge in a van. A 3 way fridge which works on gas or 240 for primary operation with 12v to keep things at temp while travelling or yoy can have a compressor fridge which runs on 12v they work really well but you need at least 2 x 120ah batteries and a 400w min of solar if you want to off grid....


Search on here willgive you some good threads to read.

You cannot run your 3 way on gas or your HWS when your driving, not only illegal but dangerous and stupid.....you could go boom.

 

[Boots in Action]

Hi all,

So we ended up placing order for a Jayco Journey Outback (15.48-6). Yay.
So now I'm planning for the future as I have a 6 week trip planned (assuming virus is gone) very shortly after I take delivery. I want to be ready.

I have a 70Ah lithium battery in the boot of the Prado that runs my fridge.
It has been running off a VSR and alternator for a few years successfully, but I feel the lack of proper charging is affecting it (I top it up here and there with 240V Victron charger).
I am planning on putting an Enerdrive dcdc in the boot to charge the battery properly and with solar if needed.

I also bought an additional 100Ah lithium for the camper that I never built, then intending to put it in van to run the fridge and TV.
Now the caravan threw a spanner in the works as Jayco only allow the BMPRO J35D (lithium capable) BMS on the Adventurer and Silverline models.
Therefore I'm stuck with J35B which is AGM only and a spare 100Ah LiFePO4. What would you do?
(PS. I intend to use the standard AGM in the van for lighting and charging devices and use the 100Ah lithium for TV and fridge duties in the van).

1. Easiest is to keep lithium in my car and just plonk another AGM in the van bringing it up to 250Amps. Cheapest option. Easiest option. Heaviest option. Will 250Ah AGM deal running fridge, TV, lighting and charging phones for 2-3 days (Van has 160W solar too).

2. Put the 100Ah lithium in the van and just run cables from the boot battery to simultaneously charge the van lithium leaving the stock AGM system alone.

3. Get 2 Enerdrive units, one for the car and one for the van. Most expensive option. Well apart from purchasing the J35D standalone for $1000.

4. Do I just bypass the whole J35B and use an enerdrive instead with a fuse box for all the plugs. And also would need AC charger. Hard to justify.

I dont want to totally dismantle the standard system as it is already wired up and monitors everything conveniently. I'm also trying to avoid weight (more AGM) as they have a poor payload as it is.

What are your thoughts.
Thank you
(All this is because I read everywhere that gas does not cool anywhere as well as electric.)

Hi there @shmick and welcome to the forum. @Drover has already provided a lot of the answers to you about the different types of fridges. Just for the record, I recently did a test on my "smaller" Thetford 93L 3 way fridge which gives a good idea of 3 way fridge operation. Furthermore, I have just come back from a 4 day camp off grid. The freezer on my fridge reached an incredible minus 24.8C running empty and averaged around minus 22.0C when loaded with ice cream, frozen Spag bol, sausages and other food I could squeeze in while off grid. So no trouble keeping FROZEN goods "hard as a rock"! Takes a day to pull down to this temp before travelling but once cold stays at the low temp in the freezer even when extra food added (chilled at least) . The fridge section is a different matter and subject to volatile temperature changes caused by frequent /(unnecessary) door opening and/or the loading of warm (air temp) foods and drinks. Recovery in the fridge section is slow in this regard, but capable of cooling to 2.0C to 4.0C overnight . That is where a compressor fridge excels in FAST pull down in the freezer and fridge sections. However, this is at the expense of high current usage which means you have to have lots of battery storage and generating power (solar/240 volt grid ) to maintain operation. More than 2 days without good solar generation and you would be pushing your luck to maintain enough battery power to continue compressor fridge satisfactory operation. There are lots of threads and posts by various members on this site if you care to go back and look for them. See my test - Electrical - Full test of Thetford 93L 3 way fridge in my Penguin dated 24th February, 2020. Tread your own path!

 

[shmick]

Great info. Thank you. So it seems to me that I will just keep frequently used items like drinks in the car fridge and just keep food in the van as it will only be accessed 2-3 times a day. The van will have the standard 95l fridge. I believe they are using the dometic, but cant be too sure. I didnt ask.
So in that scenario I might just leave the standard system and see how it goes for the first year and reassess after I get a better idea of how we use the van.
I might just invest in a solar blanket to help charge both van and car when parked.

 

[Drover]

Ideally a 2 door fridge/freezer set up is good, if kids keep opening the door all the time like the fridge at home it dumps the cold onto the floor but being smaller unit it takes longer to pull the temp down again, keeping the fridge about 75% full is best, and run the fridge for 24hrs before use on 240 then load gear cold stuff, if you can get another 12hrs on 240 before you head off everything will be nicely chilled down as the 12v from the car will keep it at temp but won't pull the temp down............... fans at the back of the unit really help the unit and keeping that side in the shade.

If you decide later to go for a compressor fridge well you should sit down when you look at the catalogues, these fridges are not cheap.......

We mostly off grid camp, TV and Foxbox run on 12v along with everything else, fridge works on gas have a small 400w invertor to charge laptop and drill all this runs from 200w on roof, 120w on the ground keeping the 210ah of AGM charged up, only get into trouble after about 3 days of solid cloud, my old ute had 80w of solar on roof to keep aux battery charged and ran an engel, but sometimes when the van was juiced up I would plug the portable into the ute to charge the aux better.................... in dire straights or for washing machine the Honda would come online ....... being quite happy to have plunger coffee I had no need to spend zillions on extra power to run an invertor for a coffee cafe............

 

[Boots in Action]

Ideally a 2 door fridge/freezer set up is good, if kids keep opening the door all the time like the fridge at home it dumps the cold onto the floor but being smaller unit it takes longer to pull the temp down again, keeping the fridge about 75% full is best, and run the fridge for 24hrs before use on 240 then load gear cold stuff, if you can get another 12hrs on 240 before you head off everything will be nicely chilled down as the 12v from the car will keep it at temp but won't pull the temp down............... fans at the back of the unit really help the unit and keeping that side in the shade.

If you decide later to go for a compressor fridge well you should sit down when you look at the catalogues, these fridges are not cheap.......

We mostly off grid camp, TV and Foxbox run on 12v along with everything else, fridge works on gas have a small 400w invertor to charge laptop and drill all this runs from 200w on roof, 120w on the ground keeping the 210ah of AGM charged up, only get into trouble after about 3 days of solid cloud, my old ute had 80w of solar on roof to keep aux battery charged and ran an engel, but sometimes when the van was juiced up I would plug the portable into the ute to charge the aux better.................... in dire straights or for washing machine the Honda would come online ....... being quite happy to have plunger coffee I had no need to spend zillions on extra power to run an invertor for a coffee cafe............

@shmick , @Drover has a good point in having a 2 door 3 way fridge instead of the smaller 93L single door. With the 2 door, you only have to open the fridge section when you want access to something, the freezer stays closed or vice versa. The single door provides access to both the freezer section and the fridge section, although the freezer section has its own small door. The most important thing to remember is that while the freezer section always remains cold (freezing), it has first priority to the refrigerant. The fridge section only gets what's left of refrigerant capacity, and therefore has less ability to pull down/cool the larger area of fridge section at any time. My Daughter has a Dometic 2 door fridge (148L ???) which can be fitted in your new van. Note how cooling can be improved with fans at back of fridge and if, and a very important IF , Jayco have fitted fridge properly according to Manufacturer's instructions, mostly they don't!!!. There are plenty of posts on this also. Just ask if you need more info.

 

[Brente1982]

Ah the old 'want to run fridge off battery' topic. 3 way fridges are absorbtion, 2 way fridges (like the one in your car) is a compressor (like your house one).

As for the bmpro J35D, the dealer I'm going through have said they will fit it to my expanda. I've made sure of it a couple of times as another dealer and jayco head office said they will not fit it.
The reason I want it is to fit lithiums after I take delivery (thus giving myself a couple of extra kg's payload.

 

[Drover]

(thus giving myself a couple of extra kg's payload.

You will still have too much weight , its Murphys Law..............

 

[Brente1982]

Lol, probably. But time will tell.
I'd like to think that my time in the infantry taught me that packing only what is necassary will hold true and generally still does these days

 

[Drover]

Lol, probably. But time will tell.
I'd like to think that my time in the infantry taught me that packing only what is necassary will hold true and generally still does these days

Of course , the van is for the Missus while you roll out a Hooch under the annex.....lol,lol,..... It really means you know how to pack the most into a small space as well , my Army time taught me how to cram heaps into a matchbox, similar as a Sailor really while as an Airman I just got a bigger truck... Dont forget the pics...

 

[Brente1982]

Oh she's partial to a swag aswell. Doesn't kind roughing it at all. Same with the kids. A caravan with an ensuite will be a much appreciated luxury. Pics of......?

 

[losheig]

Great data. Thank you. So it seems to me that I will simply hold often used items like beverages within the car fridge and just keep meals within the van as it will simplest be accessed 2-3 instances a day to find the backpack chair. The van will have the usual 95l refrigerator. I trust they may be the use of the dometic, however cant be too sure. I didnt ask.

 

[Boots in Action]

Hi @losheig , it does not really matter whether Dometic or Thetford. One very important thing to check is "Climate Class". If you are ever thinking of travelling in hot climates demand one with a "T" Rating - suitable for tropical conditions. "ST" is for subtropical conditions and ""SN" for colder conditions. All categories are tested to operate in these various conditions - up to 43C. There is a site which explains all this for you. Suggest you have a look and make sure you get the one you need.

ow do Climate Class Ratings Work?
As briefly mentioned earlier, climate class rating refers to the maximum temperature that a caravan fridge can work in. It is the European Committee for Standardization (CEN) that sets the standard climate class ratings for fridge performance wherein:

• “SN” and “N” ratings, respectively, referring to Subnormal and Normal, are caravan fridges designed and rated to work up to 32 degrees Celsius.

• “ST” or subtropical rating specifically refers to fridges that can work up to 36 degrees Celsius.
• “T” or tropical rating, as mentioned in the early part of the article, is for fridges that can work up to 43 degrees Celsius.

Basically, the maximum temperature a climate class rated fridge can work on depends on the highest ambient temperature in the air. As long as ambient temperature is within the maximum, cooling performance will be good. However, if the ambient temperature goes beyond the climate class rating, then cooling efficiency is affected.
To give you an idea, if the outside temperature is 42 degrees Celsius and your caravan fridge is rated for 32 degrees Celsius maximum, then the drinks inside the fridge will be 10 degrees warmer.
If you plan to use your motorhome to drive to places known to be extremely hot, make sure your caravan fridge is “T” rated. It’s good to note, though, that climate class rating is not something mandatorily observed in Australia.

 

[Brente1982]

Why not just ask for an upgrade to a compressor alternative? Its what im doing in the van im ordering. Its a $100 cost to go from the 3way Dometic RUA 5208X to the 2way Dometic RUC 5208X.

I have noticed that all of the new dometic rv fridges come as standard Tropical rated climate class. So theres 1 positive.

 

[Boots in Action]

Why not just ask for an upgrade to a compressor alternative? Its what im doing in the van im ordering. Its a $100 cost to go from the 3way Dometic RUA 5208X to the 2way Dometic RUC 5208X.

I guess it is power supply and battery storage for @losheig @Brente1982 ??

 

[Brente1982]

I guess it is power supply and battery storage for @losheig @Brente1982 ??

Yes potentially. Not sure if its a used or new van either.
Caravan manufacturers dont advertise the fact that there is generally a compressor alternative available either. I only found out by looking on the dometic website itself and then asking the question.

 

[Boots in Action]

Yes potentially. Not sure if its a used or new van either.
Caravan manufacturers dont advertise the fact that there is generally a compressor alternative available either. I only found out by looking on the dometic website itself and then asking the question.

@Brente1982 , @losheig is only talking about the much smaller 93L absorption fridge I think. The models you referred to are 150L which would mean modifications to fit larger fridge (absorption or compressor type), plus the extra costs of Lithium/AGM batteries and upgraded solar charging to work satisfactorily. I don't think he has any intentions of outlaying those extra dollars (like your setup) at the present time. IMHO, he should be able to use what he has as long as within the limits of equipment and understands the limitations.
I get by with what I have: 580W of portable solar panels (3) in series, 30A MPPT controller, one 120ah AGM and two 3 way fridges 92L (in van) and 36L outside (both highly modified) but running on gas when off grid, power consumption/generation on daily average can be as high as approx 50ah, and have not been caught out yet whatever the weather, even up to 40C in the shade and cloudy conditions. Admittedly, van is usually shaded (hence the use of portable panels) and fridge temps during day (opening and closing for meals, drinks/replacements etc) do rise to 6 or 7C. However, freezer section never drops below minus 18C regardless of fridge operation or ambient temperature and overnight, both fridges pull down fridge section to 2 to 4C by morning. Will never be able to meet compressor fridge operation on fast pull down time or temperature recovery time, but current system meets my requirements and does not cost me the earth. Horses for courses as I do not have the spare cash to start from scratch.