Journey Electrical upgrades JJOB

[Drover]

Yep, clear as mud... ............... The fridge draws milli amps for the circuit board but the fans will draw maybe .5a, I think when my fridge is running and thats fridge circuit and one internal fan its under 1a but when all 3 of mine are going a bit over an amp I think is used but when the externals are roaring away there's plenty of sun so not a battery draw down......... as mentioned before I generally charge phones and laptop from 1100 but if going to be a nice sunny day do it whenever, my batteries are usually in float by 0900 when I have the portable out, on overcast days though it can take longer of course ............. its really at night with the TV on, extra speakers and lights, in my daughters van they have something like 12 overhead lights and about 6 other lights, they may be led but certainly draw a heap, place can be lit up like a footy field. The fridge has 2 12v DC draws one D+ which is how it monitors if tug is connected, so solely from tug the pther for the circuit board to run the show once you turn it on, it draws from a dedicated van supply, draws bugga all, the terminal block at rear of fridge marked house 12vDC is its origin, fans may be hooked up to this block as well... If the fridge supply is a worry then you need more storage ....................

I would note though that the BM Pro 35 B - D, solar input voltage is maxxxed at 25amp so I wouldn't be hooking up in series .. unless using a seperate reg which can handle more volts and is direct connect to batteries.

 

[Hitting the road]

I would note though that the BM Pro 35 B - D, solar input voltage is maxxxed at 25amp so I wouldn't be hooking up in series .. unless using a seperate reg which can handle more volts and is direct connect to batteries

I've got the panels in series running direct to the batteries thru a separate regulator and a shunt as the BM Pro J35B wouldn't handle a high input voltage at all,..the specs only give max amperage in of 20A 0r 300w solar, either way I doubt it would have the capacity to modify 43 odd volts going in to covert to amps. So only the factory roof panel of 160w is thru the BMPro.
Besides, the specs also don't reveal whether the inbuilt solar regulator of the BMPro is of the PWM or MPPT type... internet searches don't reveal either...does anyone know? Me thinks it might even be a PWM type being the roof panel is only 160w, and the unit has a max input of 300w.

I didn't turn on the fans with the fridge when checking current draw...I overlooked doing that! The 2 door Thetford fridge I have in the van has two small computer type 100mm 12v fans at the back under the coils, I can turn on one or both...when turned on the internal fan starts as well...so draw would have to be at least 0.5v
Thats besides the 120mm fan I have added inside the upper vent...

 

[Drover]

Whether its mppt or pwm I would be chucking some more on the roof as its not always convenient to chuck out the portables, if your set up is pumping away for ages of a morning at high amps then you need more storage, I doubt it with yours, mine has 440w on roof, in theory thats 24amp, depending on voltage feed, best Ive seen on a test with dischged batteries (12.3) is I think 11 or 12 then only for a short time, portable 120 might be about 4.?a, both together once I did spy 16 when I ran compressor to do tyres as too lazy to move the tug....

 

[Hitting the road]

Portable panels admittedly can be a pita at times...putting them out then moving them 2 - 3 times a day just to follow the sun. Especially if only staying put for a day or so before moving on and needing to keep power up.
That said, I do prefer them to fixed panels on the roof as fixed panels are always compromised being the ideal angle for panels in Australia is at 30 degrees rather than 90. I can also move the portable panels a fair way from the van if need be to find the sun. I have around 10 metres of 8awg cabling to run between the van and the panels. ...compromises eh...

I will be adding extra panel to the roof, but at this point I might wait a bit until I get a better idea of where I will go as far as Lithium power and fitting an inverter. I could plug and play the next model up BMPro J35D that has Lithium battery capability and can also handle 450w solar input. That could mean 2 x 200w panels, on the roof but then being a pop top type van, weight of the roof comes in to play too for lifting.
It already has an air conditioner, TV antenna and a solar panel, internal lights etc, easy enough for me to lift but going forward... Fortunately the air conditioner is mounted about centre so lifting is not of the whole weight at once, a bit each end...

 

[Drover]

You know where your heading, looks good to me but I wouldnt fork out for a BM Pro D, my Epever is lithium capable and could buy 3 for BMPro D's price . I cannot see any value in spending that much. Unless weight is an issue lithiums aren't good value at the moment... There are some lithiums which have a very cluey BMS and are happy to charge at an AGM setting, of course you pay for it....

 

[Hitting the road]

I hear you...I was only really thinking of the ease of the upgrade of a BMPro J35B to the newer J35D...pretty well plug'n'nplay. The existing wiring apparently will connect straight up without making any changes or alterations to any connectors...knowing though that they certainly are not the Bee's knees when it comes to a BMS. I think even Jayco may have moved away from the BMPro BMS?

Jayco also say in their sales blurb that their 2022 models have a "new" MPPT solar system that's capable of up to 20% improvement in power output. That tells me the previous models including mine must have a built in PWM type solar regulator...which would indicate too even their J35D likely has a PWM type controller built in. No biggy really, 'cept one is not going to get the best out of their panels...
...that in itself could be a very good reason to look for an alternative Lithium capable and better BMS...maybe with an MPPT regulator built in.

But again...it's just as easy to run all the solar including the roof panels through a separate MPPT rather than through the BMS itself. I will be doing some serious research and doing the sums, I definitely don't want to rush off and waste my hard earned on a second rate power management system!

 

[Drover]

The only change between a "B" and a "D" that I can see is it gives the extra juice for lithium, still restricted to whatever the solar output is, which really is academic anyway..... If you go lithiums I would just add a decent MPPT reg and just use the BM Pro as a power distribution system.

I don't have any BMS, so have saved heaps, my Epever solar Reg charges the batteries and a fuse board distributes the power, regulated by a few switches, a 240v charger sits there doing nothing, a panel connected to my Epever replaces the voltmeter I once had, it shows where and what is being used, real world not some guess work algorithum ............... even when I had just 200w of solar and a PWM Morningstar reg my batteries were kept up to speed and never needed charging from tug, it wasn't possible anyway, I always think if you want to off grid then charging from tug is a bit strange unless of course your panels are all portable, if you leave home you should have fridge chilled down and batteries charged, my concerns camping are water, gas and beer............. I do not like all in one blingy systems no redundancy one bits fails the whole lot dies................ mine doesn't.

 

[Hitting the road]

I like that idea Drover. A "Battery Management System" imo isn't necessary either. I guess they have become popular so the folk who aren't interested in what goes on in the cupboard or under a seat can just plug in when they get to a Park and let the system take over. Plus now with the fitting of masses of solar panels to roofs some sort of BMS further takes away any required input from the consumer to oversee. I prefer to "manage" my power supply...

I 100% agree that in order of camping importance...1; water, 2: gas, then 3: booze... I agree too that with proper power management charging van batteries from the tug should not be necessary...fact is I just failed myself last time when I was pulling power from the batteries but putting nothing back in to replace.

 

[Drover]

When I plug in to 240 its only replacing gas that we would use, everything else runs off the batteries/solar of course it replaces the genny for the washing machine and AC....... its an ideal time to check how much you burn and is surprising in that its usually less than if you guestimate............ one thing I would also do maths on is fridge gas burn, just divide the Mj the fridge burns per hr by 400 and thats how long your 8.5 bottle will last , ( if oyur fridge has it in grams /hr then Google is your friend) mine comes out empty bottle after 11 days, which is correct too, so with a bit of cooking and HWS I get ready for it to be empty on Day 8-9, longer if less HWS or stove use but thats a location/weather thing... so by day 14 I want a new bottle in the rack on stand by..... have carried an empty with me for trips where we may camp somewhere for a fortnight or so, fill it for $30 before I head into the never never where it will be $55 or more ...

 

[Hitting the road]

Did some sums...my Thetford fridge according to the manual will burn 420 grams of gas per 24 hours at 25 degrees ambient, so reality may even be 450g...apparently, water heater around 2 grams per hour if the 8.7mj per hour is correct.
I use a Weber type BBQ connected to the van's gas outlet for some cooking...not using the stove inside the van at all preferring a separate portable gas type cooker outside for day to day.
I reckon 8.5kg's of gas will last me around 15 days with normal usage off grid...so with the 2 x 8.5kg bottles on board should give me close to a month in total. Real life use would be the only way to know for sure, but even that could change if there was a small gas leakage or a bottle isn't full.

Power usage on paper I calculate 22 Amps per 24 hours with normal usage inc 3 hrs of lights at night, phone charging, water heater, water pump, sirocco, and allowing for some leakage....maybe make it 24 amps for good measure.
So....with 280 amps of battery storage if they were 100% full and new...lets make that 250 amps as I doubt they would ever be 280 amps anyway...that's 125 available, divided by 24 = just over 5 days if nothing went back in to be at 50%.
My panels should easily put that back in every day anyway...

Water is always the first casualty, with only 160 litres on board in the tanks, average water use 22 litres per day, I'd be looking for water after just 7 days off grid...

 

[Drover]

1kg of LPG is 1.96lts , 1lt of LPG is 510 grams ........... so I'll let you do the maths, .................................... I think you have less than you think but that may be my maths .... ... mine is in Mj ................

Water all depends where you are and when 2 tanks can be gone in a couple of days or when out back of Innaminka can last weeks............. Your power usage sounds about right but it does float around a bit and you don;t need that many lights on either, i always wonder at these folk that have the outside light on for hours , nobody is outside either.................. Now that you have figured it out, you then just glance at the panel and enjoy camping, no need to watch like a hawk...

 

[Hitting the road]

Thanks mate...appreciate the reply. I guess eventually I'll get a better real world understanding of usage and how long things will last. Sadly won't be going anywhere between now and end of at least January after the kiddies go back to school and the weather begins to cool...so not much real world experience going to happen...though even Feb and March can be stinkers up here...will have to head South!

I plan to do the big lap starting May next year when the weather is cooler, so knowing how long things will last will be pretty important...

 

[mikerezny]

Did some sums...my Thetford fridge according to the manual will burn 420 grams of gas per 24 hours at 25 degrees ambient, so reality may even be 450g...apparently, water heater around 2 grams per hour if the 8.7mj per hour is correct.
I use a Weber type BBQ connected to the van's gas outlet for some cooking...not using the stove inside the van at all preferring a separate portable gas type cooker outside for day to day.
I reckon 8.5kg's of gas will last me around 15 days with normal usage off grid...so with the 2 x 8.5kg bottles on board should give me close to a month in total. Real life use would be the only way to know for sure, but even that could change if there was a small gas leakage or a bottle isn't full.

Power usage on paper I calculate 22 Amps per 24 hours with normal usage inc 3 hrs of lights at night, phone charging, water heater, water pump, sirocco, and allowing for some leakage....maybe make it 24 amps for good measure.
So....with 280 amps of battery storage if they were 100% full and new...lets make that 250 amps as I doubt they would ever be 280 amps anyway...that's 125 available, divided by 24 = just over 5 days if nothing went back in to be at 50%.
My panels should easily put that back in every day anyway...

Water is always the first casualty, with only 160 litres on board in the tanks, average water use 22 litres per day, I'd be looking for water after just 7 days off grid...

Gas consumption is very much dependent on individual usage patterns.
In particular, fridge consumption is dependent on keeping the external wall behind the fridge shaded to keep the sun off and when traveling, parking the van so that, again, the sun is off that external wall.
Open the door as little as possible and keep it opened for as short as possible, especially on hot days. Don't keep items out of the fridge longer than necessary. Don't restock the fridge in the heat of the day, when the new items are at the hottest.
Try to keep the fridge filled, even with empty containers so that the minimum amount of cold air is dumped onto the floor whenever the fridge is opened.
This all sounds quite a challenge. But, we have all become very accustomed to efficient domestic compressor fridges with plenty of reserve capacity. It will stay cold regardless of how we use it.
However, I was brought up as a child with a kerosene fridge when we lived on Fraser Island and, during summer, we all understood what was required to keep things cool and avoid food going off. Especially when we only got a food drop from the mainland once a fortnight. If I sometimes forgot what to do, a clip around the ears improved my memory markedly! It was my task each day to check the fridge flame was burning and to keep the container filled with kero!
I have a mate in Queensland who lives permanently off grid and has a gas fridge. It is also second nature to them to nurture their fridge especially on hot summer days.

If you don't have one, a digital thermometer with an external probe is a good investment to monitor the internal fridge temperature. I have a dial thermometer in the freezer.

It would also be worth having a good look at the rear of the fridge to see if the insulation can be improved. Main thing is to keep the heat from the boiler and the condensor fins from getting onto the sides and the top of the fridge,

cheers
Mike

 

[Drover]

Mikes on the money on nursing the fridge, actually its good practice at home as well, they may be bigger but opening the door does the same thing, dump the cold.................... thankfully our 2 door fridges don't suffer as much as the single door jobs......

After I pulled mine out and cleaned the back and modified the insulation a little bit, brushed down the dirt off the plumbing and gave it a spray of paint, it works just a little bit better I have found, dust tends to interfere with the removal of heat..amazing..................... if you ever do a job on the back of the fridge don't pack the side walls with insulation, just a small sausage of insulation around the back edge to seal the side from the back, otherwise it seems you can get a lot of condensation on the sides with problems of rust/mould as the fridge side sweats ............. just must have the back sealed off so heat goes straigt out the upper vent and not circulate around the fridge, keeps the dust out as well..... and never seal the vents up on dusty roads, just dumb if dust gets into the van that way then its not fitted properly.... and beer gets hot.

While you can buy fancy little screens (expensive) to cover the outside wall of the fridge they are often too small and not really effective . I have a sail trak running the length of the van and slip a awning shade screen along it, keeps the shade on the fridge wall all the time and helps keep that side of the van cool.... use an Aldi 18ft screen and it was cheaper than a fridge screen which is only a metre wide................. Some camps I will veen throw a few buckets of river water over the outer wall even seen a fella with a small solar pump his home made sprinkler spraying over the wall, we stood next too it while having a beer, most refreshing...

 

[Hitting the road]

Very good tips, thanks...I have one of those fridge thermometers that has a sender unit in both the fridge section and the freezer monitoring temps, thanks to Boots in Action's tip a while back.
When i am using refrigerated items I take them all out, such as butter, cold meat, cheese etc all at once, then put them all back at the same time rather than open and close the fridge with each item...just opening the door twice, not multiple times.

It is not surprising to see the fridge and freezer temps increase by up 5 degrees or more during the day when sun falls on that outer wall. It will change quite noticeably when putting anything in there that is not at a lower temp. I always make sure I re stock the fridge with beer or wine in the evening for the following day so it has all night in the cooler air to chill...

The van has a sail track the full length of the wall and I have a screen to go in it too, but to date I haven't fitted it. The other week when camping I should have as the afternoon sun was belting on that wall and fridge temps were quite badly affected.
The plumbing behind the fridge is clear of dust but the piping does have some surface rust and scale on it that I do need to clean off. The 2 x 100mm fans that are under the fins don't do an awful lot to assist I have found...

 

[Drover]

Mine was 10 years old when I cleaned mine out and honestly wasn't all that bad really, the fans at the back ideally should be above the condensor fins, that way they create a low pressure below and increase air flow over the hot bits and easily force the air out the vent, some I see have them positioned below which means the fans do all the work trying to push air ... I have fitted mine to the actual vent and you can really feel the hot pumping out when fired up, I used to have a thermo switch on them but when it failed I didn't replace it now I just turn them on in morning and off of an evening when its warm... used a70 deg switch as a 50 deg the things came on and stayed on.
My screen is just pegged to ground with Okky straps, then when the wind blows they can move a little bit and not pull pegs out if tied down with rope.

 

[mikerezny]

I always make sure I re stock the fridge with beer or wine in the evening for the following day so it has all night in the cooler air to chill..

I initially did this, until I realised that I was putting items in when they were the hottest.
What I do now is to store items in the coolest place then leave them out overnight to cool down in the cooler air, then put them in the fridge early in the morning.
If I have to put in quite a few items this won't work since the fridge won't recover before the heat of the day. If this is the case, I put some in just before I go to bed and the remainder go in the fridge early in the morning.

Yes, it is good to be able to monitor fridge and freezer temperatures. One can quickly see the effects of opening doors, putting in new items, and get a feel for how long the fridge takes to recover. I admit I spent far too much time in the first years micro managing the fridge. But, armed with that experience, it is all much easier now. Notably, we have never had to throw anything out or worry about things in the fridge getting frozen.
Our fridge is a manual 95l Dometic. These have a habit of ice buildup on the fridge compartment condenser fins. This is problematic since ice buildup near the thermostat prevents the fridge from regulating the temperature correctly since the controller thinks the fridge compartment is colder than it actually is. This starts to become noticeable around a week into a trip. One solution is to have a fridge fan under those fins to circulate the warmer fridge air over the fins to melt the ice. I have a small portable personal fan that does the job. But over the years I have found it unnecessary. I now turn the fridge temp setting up a little warmer for an hour or so in the evening when I notice ice building up.

cheers
Mike

 

[Drover]

Also ideal fridge temp is 0 to 4 deg and freezer is anything of minus 12 or below ...

 

[Hitting the road]

The fridge is usually between 4 & 6 degrees in the morrning and the freezer around the -14 to -16 mark. During the day the fridge is usually around the 7 - 10 degrees and the freezer will get as high as -8 or so when sun hits the side wall.
I have put a 120mm fan in the upper vent with a 60 degree thermostat, but it has not come on yet that i am aware of. When I feel the temp of the pipe I have it attached it to is not too hot to touch, so I need to move the thermostat to a pipe that cools and heats but away from the "chimney".

The 2 little 100mm fans in below the fins as you note Drover don't really do an awful lot...when on yes you can feel a bit of a draft if you put your hand in behind the fridge, but it's not cyclonic by any means.

 

[mikerezny]

The fridge is usually between 4 & 6 degrees in the morrning and the freezer around the -14 to -16 mark. During the day the fridge is usually around the 7 - 10 degrees and the freezer will get as high as -8 or so when sun hits the side wall.
I have put a 120mm fan in the upper vent with a 60 degree thermostat, but it has not come on yet that i am aware of. When I feel the temp of the pipe I have it attached it to is not too hot to touch, so I need to move the thermostat to a pipe that cools and heats but away from the "chimney".

The 2 little 100mm fans in below the fins as you note Drover don't really do an awful lot...when on yes you can feel a bit of a draft if you put your hand in behind the fridge, but it's not cyclonic by any means.

Have the 100mm fans got a shroud around them? If not, then the fans are probably just pumping air from the back to the front.
There are two options, make a shroud around 100mm long to go on top of the fans to direct air up as directly as practicable onto the condensation fins. Ensure that the fans are off to the left as far as practicable. i.e as far away from the boiler so the inflow is not getting hot air from the boiler.
Also over to the left is where they will do the most good as that is where the fins are the hottest.
Similarly with mounting a fan on the top external vent. There is no point putting in two fans as the second fan will be mounted on the right and will just draw hot air up from over the boiler. I experimented a lot with fans and I am of the opinion that a good quiet 120mm fan mounted over on the left provides the best cooling. (caveat, unless you want to go to the trouble of putting in a wall to ensure that the boiler is thermally isolated from the LHS of the fridge. The lesson is that getting only the cool air from the bottom vent up to the condenser fins is more important than getting a lot of air over the fins.

Look for the dimpled pipe that comes off the top of the boiler and head left across the top of the fins and then into the condensation fins. The thermostat is placed over on the LHS of this pipe. A 60C thermostat is probably too high. I use a 55C thermostat.
Her is a link to one of my early posts when I first installed the fan:

https://www.expandasdownunder.com/threads/quiet-fridge-fan.9619/post-170065

This post shows the location of the thermostat.
https://www.expandasdownunder.com/threads/dometic-3-way-fridge.10180/post-175505

cheers
Mike