Supreme caravan charging issues

Submitted: Thursday, May 02, 2013 at 18:07
ThreadID: 101982 Views:5437 Replies:10 FollowUps:9
This Thread has been Archived
We have a new supreme caravan with a vitrifrigo compressor fridge. We have two 97 amp hour batteries and two120 watt solar panels. When we run the fridge for a few days it drains the batteries to almost flat( solar control cuts out at 10.7 v). Solar controller says the fridge draws around 2 amps. I would have thought the solar would keep up a little better. Other issue is even if I have the 240 connected the biantech 25amp 3 stage charger won't bring them back to full charge. The charger says it is for lead acid only and the batteries are calcium. Supreme seem to have no idea what so ever about auto electrics and I am worried they have got the wrong charger in the van. They also set the solar to cut out at 13.7 v and all the battery shops tell me these deep cycles need 14 plus volts to fully charge.
We leave for our round aus trip this week and free camping is looking sick if we can't charge our batteries.
Back Expand Un-Read 0 Moderator

Reply By: Motherhen - Thursday, May 02, 2013 at 18:39

Thursday, May 02, 2013 at 18:39
Hi Sam

What size is your fridge?

What amps do you see coming in from the solar?

Weather conditions and whether you were parked/travelling in the open or in shady conditions would also have an effect.

I have set our controller to 14 v for our AGM batteries. It could go a little higher, but we have a trickle charge form the battery so left and allowance for that.


Red desert dreaming

Lifetime Member
My Profile  My Blog  Send Message

AnswerID: 510210

Follow Up By: sam h6 - Thursday, May 02, 2013 at 18:45

Thursday, May 02, 2013 at 18:45
230l. It has been parked in our yard in Tassie. Mostly sunny sky's all week. Only the fridge running and out side temps mid teens. Frost over night. Most of the time it shows .8 ish of amp going out to a max of 2 amp at start up. When charging even till last sun in the arvo it shows up from 2 to 5 amp and in full midday sun up to 10-11 amp.
FollowupID: 788283

Follow Up By: Motherhen - Thursday, May 02, 2013 at 18:54

Thursday, May 02, 2013 at 18:54
That is a larger than our 130 litre Vitrifrigo, but I would have expected better. The Tasmanian sun charged our solar very well.


Red desert dreaming

Lifetime Member
My Profile  My Blog  Send Message

FollowupID: 788284

Follow Up By: Member - Arsenal Phill - Thursday, May 02, 2013 at 19:15

Thursday, May 02, 2013 at 19:15
We have a 220l Virtigo Fridge/Freezer compressor style. We think it is great. Our van has x2 120AMP Hour batteries. We do however have x3 150W solar panels. To date we've never had power issues. Generally after a night, the batteries are back to full charge by 10-11 am. Our solar controller is a 30amp.

Maybe you may just need to increase your panels??
FollowupID: 788287

Reply By: Member - Scrubby (VIC) - Thursday, May 02, 2013 at 22:42

Thursday, May 02, 2013 at 22:42
G`day sam h6,

If what I understand about calcium batteries is correct, (quite often I am wrong, and I hope someone here will correct me if I am)
For the solar to charge a calcium battery to 100% charged it will need to deliver a minimum of 15.1 volts at the battery.
The 25 amp 3 stage charger will have to deliver the same voltage (15.1 volts) with the 3rd stage, ie the float charge stage.

Calcium Batteries are lead acid batteries, the lead plates have a small percentage of calcium in them.
They are supposed to have heaps of advantages that the marketing people are only too willing to sprook about. Then there are others that are ignorant of the specifications.
What they DON`T tell you is that very few vehicles have an alternator capable of supplying sufficient voltage, 15 volts +, to FULLY charge them.
I refuse to use a Calcium Battery.

AnswerID: 510217

Follow Up By: Member - graeme W (WA) - Friday, May 03, 2013 at 22:07

Friday, May 03, 2013 at 22:07
Scubby is correct. Coromal supplied there vans until recently with lead calcium batteries.(they are cheap) with a charger that has written on it not suitable for lead calcium batteries. In this case if all the wiring and regulator are up to scratch then the batteries are probibly stuffed. My next door neibour had the same issue with his coromal. Now that he has an AGM battery no probs. Because the calcium batteries never charged properly they fail quickly. They were never meant to be discharged and recharged and i would never use one either. Some of the worst advice comes from battery sellers and van and camper sellers. That includes cable size and battery selection.
Just my experience.
Cheers graeme.
FollowupID: 788359

Reply By: Racey - Thursday, May 02, 2013 at 22:53

Thursday, May 02, 2013 at 22:53
Sam, A couple of points.

1. Is the frig empty? An empty frig will consume a lot of energy due to a low thermal mass.

2. Calcium batteries require an equalizing setting of 16 volts. The normal bulk charge should be at least 14.4 volts followed by a float of 13.8 volts.

3. The settings of the 240 volt charger and the solar controller need to be reviewed.
you refer to a Baintech charger, is this a Ctek? These have a calcium battery setting. The charger should bring the batteries up to full charge. If the charger has a "power supply" setting. I suggest you switch to that setting when you get the basic problems sorted. The "power supply" setting will prevent the batteries from being over charged with a load connected. Clearly you have other issues. It almost sounds like the 240 volt charger is not contributing any charge

4.Check the solar controller manual for "battery Type" settings. If it doesn't have a calcium setting I would select "flooded" or "AGM".
can't understand why it has been set to cutout at 13.7 volts, unless this is the float voltage. What brand is the controller?

Look forward to your feed back.
AnswerID: 510218

Reply By: Ozhumvee - Friday, May 03, 2013 at 06:03

Friday, May 03, 2013 at 06:03
Like Motherhen we have a 130 L Vitrifrigo, the one with the remote compressor unit.
They use a Danfoss compressor, BD35 on ours, yours may well be a larger but similar unit.
The Danfoss controller changes the compressor revs as the load changes to minimise power usage and increase efficiency. Ours pulls anywhere from just under 4 amps down to about 1.4 depending on the load.
I reckon you have two problems, the wrong charger for the batteries if it doesn't have a Calcium setting and the wrong settings on the solar controller. As others have said calciums need a much higher voltage to charge correctly and if they are only getting 13.8v max then they are probably (guessing) that they are only 50% charged at best.
The other "problem" with the Vitrifrigo is a lack of insulation around the cabinet itself, not really designed for our climate. If you can add 50mm of insulation to the outside of the actual fridge cabinet you will notice that it runs far less and uses, in our case, approximately 25-30% less power due to shorter run times.
I just bought high density polystyrene sheet insulation (blue, also comes in a pale pink colour as well) and stuck it to the outside of the fridge, virtually doubling the wall thickness of the cabinet. If you have more space around the fridge then make it thicker again.
AnswerID: 510223

Reply By: sam h6 - Friday, May 03, 2013 at 07:01

Friday, May 03, 2013 at 07:01
Well the charger has no settings what so ever, it is simply a biantech brand no other names on it.

The solar control is a Juta and the instructions have such bad English that I struggle to follow them, obviously written by someone who speaks a different language. Before anyone rips me no I am not racist at all but this instruction book is poor.

There are no settings at all for battery types on the control. I have been all through this and it's driving me nuts. The standard response from supreme is the control should not be touched as they know how to set them up and we should not adjust them, i have since cranked it up to 14.6 volts as the label on the battery says max charge volts 14.7. also yesterday I was informed by one of their techs that running my fridge will flatten the battery in half hour, it should be run on gas. Believe it or not I had just spent 10 minutes explaining that I hade a vitrifrigo with a danfoss compressor!!! After getting a little frustrated and pointing out the issue again he replies " oh never heard of those before".

The other issue is they only run 6 mm2 wire throughout the whole system and 8 mm, not b&s just mm, to the charge plug for the vehicle. I am not a qualified auto elec but the industry I work in involves a fair bit of it and I nearly had a heart attach when I took a close look at the wiring.
AnswerID: 510224

Follow Up By: ChrisK - Friday, May 03, 2013 at 12:36

Friday, May 03, 2013 at 12:36
Have to agree with you that the caravan industry has no idea of what to do with wiring. I too have a Supreme Territory caravan that's jut over 12 month old. We have 2 x 80 watt panels on the roof but as it was a stock(off the lot) van it had a 3 way fridge. I must say that it has been fantastic and we have never had any issues with it or the gas supply. I feel for you re the controller as our's is one the same. Absolute rubbish. I am looking at replacing it with a Ctek 25 amp charger at the moment. They are supposed to be the "duck's guts" of the charger world.
Best of luck on sorting this out.
FollowupID: 788313

Follow Up By: Nomadic Navara - Friday, May 03, 2013 at 13:05

Friday, May 03, 2013 at 13:05
I'm not sure but I seem to recall that your Bainteck charger is not a proper 3 stage charger. It's more of a power supply. Has the charger dropped down from the 14.6 V you set it at? If not it will cook your battery (if it has not already done so.) Turn it back to 13.8 V or slightly less if it has not come back to a float charge.
Retired radio and electronics technician

Lifetime Member
My Profile  Send Message

FollowupID: 788317

Follow Up By: Racey - Saturday, May 04, 2013 at 09:32

Saturday, May 04, 2013 at 09:32
Sam, I looked up your controller on the internet and I agree the instructions are bad; sort of fits with the controller. Couldn't find a Baintech charger. Bainbridge sell a range of good chargers including the Ctek range. Seems to fit with a previous comment about power supplies. I would be having a serious chat with Supreme about the quality of components they use. Your set up isn't what is should be.
FollowupID: 788377

Follow Up By: Member - silvwayne - Saturday, May 04, 2013 at 17:46

Saturday, May 04, 2013 at 17:46
I have a Supreme with same charger. It is a 3 stage with a float of 13.6 volt. Have had no problems with it. Have camped for 3 days on 100 AH battery, and still had 10.9 volts in it.

FollowupID: 788401

Follow Up By: Member - Wozikev - Sunday, May 05, 2013 at 14:17

Sunday, May 05, 2013 at 14:17
My policy on 12v wiring - "I always use the biggest wire that I can get in the hole". It's possibly cost me a little extra in wire over the years but it's always looked after my fridge and batteries. I have a Redarc BMS and with my heavy wiring, I'm grinning !!

Cheers .................. Kev.
FollowupID: 788473

Reply By: Member - Rick P (NT) - Friday, May 03, 2013 at 18:46

Friday, May 03, 2013 at 18:46
Hi Sam
We have a Vitrofrigo and had major problems till we upgraded the wiring to 8mm cables to the batteries. But it sounds like you need a better charger as well, can't go past a 2500 CTec charger. Good luck it can be very frustrating getting it right.
Rick P
AnswerID: 510256

Reply By: sam h6 - Friday, May 03, 2013 at 20:09

Friday, May 03, 2013 at 20:09
Thanks to everyone for your replies it's great to get opinions from real travellers with real experience, not someone who is paid to tell me what I want to hear.
We are booked to call into the dealer Monday morning for our "first service" and sort out these issue. After reading all the replies and talking to several auto elecs today I will be pushing for a new 240 charger, and I guess I will be forking out for a new solar controller as I can't prove theirs is not fit for purpose.

If any of you in your travels see someone looking very frustrated and drinking warm CC& dry outside a supreme caravan, it will be me because the batteries have gone flat!!!
AnswerID: 510268

Reply By: dieseltojo - Friday, May 03, 2013 at 21:24

Friday, May 03, 2013 at 21:24
Hi sam,
I have a different set-up and do a lot of free camping.
Nothing is more power draining than a fridge, and I always recommend one that runs on gas if free camping, though it may not be quite as efficient.
Hot Water heater also on gas.

Glass matt batteries recharge in a few hours compared to standard deep cycle batteries, and are recommended.
My solar settles on 13.8 volts as fully charged, and I have a total of around 300 watts on the roof.
I have done many 8 week trips and never needed to run a gennie or hook up to 240 volts, including Tassie.
My biggest power use is probably computers and the TV. All lighting is low power LED.
All my wiring is above spec size wise.
It's better to have extra panels rather than three batteries to maximise solar.
That's just my system and works for me, others are free to disagree.
AnswerID: 510276

Reply By: gottabjoaken - Sunday, May 05, 2013 at 09:33

Sunday, May 05, 2013 at 09:33
I would check the power consumption of the fridge.

I believe that it will more likely be drawing up to 7 amps for anything up to 12 hours a day.
Ie 90 - 100 amp hours.

Disconnect the solar and then check the current draw.
Or check the specs.

If the wiring is not sufficient you will always struggle to provide enough power to the fridge. If it is adequate, then your batteries will always struggle to have sufficient capacity for it anyway.

You certainly do not have sufficient solar panels for that fridge.
Your panels under the best conditions will be able to supply about 6-7amps each.
That for about 5 hours on the sunniest of days adds up to a maximum of 70 amp hours.

If you are not adding to the charge with vehicle connected DC-DC charging, your fridge will consume more than the solar can ever provide.

The suggestions would be any or all of:
Replace the calcium batteries with Fullriver AGMs;
Add two more 130watt solar panels;
Ditch the solar controller and fit a couple of Morningstar Sunsaver Duo;
Rewire the fridge to use one battery and the house supply to use the other;
Check out the Charger very carefully and probably replace it with an adjustable three or four stage charger;
Add a pair of DC-DC chargers from the vehicle to better put charge into the separate batteries when driving, or one if the batteries are still connected in parallel.

Without at least replacing the mains charger it would look as though your round Aus trip is unlikely to proceed this week, and free camping will anyway be severely restricted.

AnswerID: 510351

Reply By: The Bantam - Sunday, May 05, 2013 at 09:47

Sunday, May 05, 2013 at 09:47
Be very aware there is a hell of a lot of misinformation running around about batteries and charging and what this or that battery will do....but I'll let that pass for now.

first and most important....all good changers, both solar and mains are looking for a direct relationship with a single battery.....they may tolerate a bank of batteries.

when we have two chargers connected to the same battery powered up or not we run into problems...


Do you have the solar and the 240V charger connected at the same time?......Don't.

one charger connected to any given battery at any one time...unless the system is specifically designed otherwise.

On the matter of the this a compressor bassed fridge or a 3 way fridge that will run on gas.

If it is a 3 way fridge that runs on gas, they are incredibly inefficient on either 240V or 12 volts.....on 240V who cares you are on mains......on 12 volts 3 way fridges are only viable when the engine is running, because they draw heaps and all the time.

A complication is that 3 way fridges are almost always wired to 12 volts in cable that is far too small.......efficiency then suffers.

By all means run the 3 way fridge on 12 volts when traveling, but when you stop run on gas.

On cable issues.

We live in a metric country, anybody who knows their business about electrics will be talking in square milimeters when refeering to cable.......yes there is plenty of American Wire Guage cable about, but to do any calculations we must convert to mm.

8 guage is close as damit to fact "proper 8 guage" is 7.91mm2.

On the matter of the charger......don't worry about the settings or the side issues about what voltage people claim you need to charge this or that battery.......get that battery charger hooked to the battery on its own with no solar and no other load and see how it goes.

As for the notion that you can charge a "glass mat battery in only a few hours"...that is false....SOME AGM batteries may tollerate and accepet charge faster and better than others but...there is no free lunch and some AGM have very limited charge rates.

no matter what the battery, if it is at a low state of discharge regardless of the size of the charger or battery capacity expect charging to take time think in terms 8 hours minimum or over night rather than the " few hours".

AnswerID: 510352

Sponsored Links

Popular Products (9)