Thetford/Norcold fridge - run it on 12v permanently ?

[Deleted member 62288]

another option is to not have such a pressing need for a fridge. we never had one for years when full timing , and rarely turn on the one we have now. so if you do run out of gas up a mountain , either drive to get more [it's never far] or eat the food as necessary

Thanks, N.B.

Thing with me is that I am a bit of a hedonist, I like life's pleasures and luxuries.

I'm of a technical background with a big interest in technology, if I can be eco friendly by using free solar power vs LPG or the alternator via a diesel engine, then Free solar power wins every time for me anyways.

The other 2 options produce noxious emissions after all.

I've had many periods in my life where frugality was necessary and sometimes unavoidable.

But I'm comfortably retired now and off the treadmill, I'm really lucky to be in this position and I am extremely grateful for being blessed as such.

james

 

[Deleted member 62288]

How long are you going to be on the top of this mountain in
Spain lol?

For me it's 2x13kg bottles of gas (Spanish). One bottle will last a month,
then it's time to start looking for an exchange, so say + 6 weeks static
is possible on average, much depends on season and whether space heating.
I carry a camping gas R907, belts and braces, never used it.
Relying on Gaslow may not be the best decision in isolated circumstances.

But... you can run out of sunshine for weeks up a Spanish mountain at times!

I spent 6 months in Orgiva parked up in a Damon Daybreak on a campsite, never moved the vehicle during that time.
Free electric with the pitch fees so my solar system was basically unused and I never had to worry about my fridge as it was on 220v.

I towed a Fiat Punto on a trailer, which I used to collect gas bottles, every couple of weeks.

But now I have a Hymer and I'm not currently towing a car - but if I decide to spend a long time at a place in the sun, I'll be taking a car and trailer and again, probably be on the mains.

One of my objectives is to maximise all of my options so that I have a fallback position for everything, where possible.


Relying on LPG period is not the best decision in my view, hence the search for a 12v free solar solution, currently being discussed.

Lots of good feedback, comments and suggestions, many thanks to all.

james

 

[Deleted member 62288]

Is your fridge and contents a priority ?

Is your fridge and contents a priority ?

My fridge is always crammed, even before I put fresh food into it, so is my freezer above the fridge, meat, fish, kippers a'plenty etc.

I have all of my condiments, such as Mayo, Ketchup, jams, marmalades, salad dressings etc etc plus other stuff that needs to be kept cool or refrigerated. It is an essential for me.

I don't understand how folks have an empty fridge where do you keep the ketchup bottle ?
and the butter ?

I've had several occasions in Iberia where the fridge has failed to stay cool or has decided to defrost itself and having to throw out almost everything is not something I want to have to keep doing because I can't fuel the fridge.

So the basic choice is not between LPG or 12v Solar, my choice is to facilitate both for static periods and bonus of engine alternator when driving and 220v on an EHU.

All risks understood, identified and mitigated,

 

[Canalsman]

Earlier you say that your fridge is a compressor fridge. That, of course, isn't the case.

There are three significant drawbacks to 12v operation. It uses a lot of current, it doesn't cool very well and it's not thermostatically controlled.

Running on gas and 240v your fridge may well be thermostatically controlled. If so, I would suggest use of a small high efficiency inverter to power the fridge is probably a better option if you want to make use of solar energy that is otherwise not harvested.

If your fridge has auto energy selection you could refine this further by using a 12v time switch to power on the inverter during daylight hours and then fall back to gas usage when dark.

 

[n brown]

i spent a bit of time at Orgiva , not on a campsite but on the river bank with all the other travellers., so we didn't use the fridge , just had a nice daily stroll up to the village for fresh provisions and a coffee beer etc stayed cold in a bag in the river. i like to be comfy too !

 

[Byronic]

Take my simple 'solution' to the energy problem ie 2x13 kg gas bottles plus
the R907 emergency bottle. 2x120A leisure batteries, 3x80W solar panels.
Mainly used in southern Spanish winters, and mostly on the coast, where the
sun usually shines best.


Outline a realistic situation in which you would envisage struggling with
my set up. Just asking, I enjoy gaining knowledge, no ulterior motive!

 

[Deleted member 62288]

Earlier you say that your fridge is a compressor fridge. That, of course, isn't the case.

There are three significant drawbacks to 12v operation. It uses a lot of current, it doesn't cool very well and it's not thermostatically controlled.

Running on gas and 240v your fridge may well be thermostatically controlled. If so, I would suggest use of a small high efficiency inverter to power the fridge is probably a better option if you want to make use of solar energy that is otherwise not harvested.

If your fridge has auto energy selection you could refine this further by using a 12v time switch to power on the inverter during daylight hours and then fall back to gas usage when dark.

I believed it is a vintage 2004 compresser fridge, but I've just found the label which tells me its an N145 which is a 3 way absorption fridge, I've updated my memory banks - thank you for the correction.

It is 147watts at 12v.

I will explore the inverter route also, it was already in the plan.
I have a 1000 watt psw inverter that I've robbed off my caravan, it's purpose there was to back up the fridge during power loss or travel (or when the pound coins expire in the meter and it's raining, dark and muddy.).

I'm still looking for an easy way to fool the EBL to switch on the power to the fridge any ideas ?

 

[Deleted member 62288]

Take my simple 'solution' to the energy problem ie 2x13 kg gas bottles plus
the R907 emergency bottle. 2x120A leisure batteries, 3x80W solar panels.
Mainly used in southern Spanish winters, and mostly on the coast, where the
sun usually shines best.


Outline a realistic situation in which you would envisage struggling with
my set up. Just asking, I enjoy gaining knowledge, no ulterior motive!

I'm not disagreeing with you, your set up is similar to mine.

My current topic is how do I run my fridge on 12v permanently ?

so how do you run your fridge ? on LPG.

That doesn't answer my question.

 

[n brown]

don't have an EBL but have a relay that channels charge from the solar to the van battery when the leisure batteries are fully charged ,and this often fools my split charge relay into thinking the engine's running and turns my fridge on. i have put an led light on my fridge to let me know when it receives charge in this way and it seems any reasonably bright day will do it

 

[Deleted member 62288]

i spent a bit of time at Orgiva , not on a campsite but on the river bank with all the other travellers., so we didn't use the fridge , just had a nice daily stroll up to the village for fresh provisions and a coffee beer etc stayed cold in a bag in the river. i like to be comfy too !

I went down into the river bed area, and got to know a few of the folks involved in the Dragon Festivals.
Still a couple of coach conversions in place - that was 2012.

My neighbour was Nick who was living in his old blue bus come sound/PA system lovely home build, very nice bloke with his old hound Nico.
Jorge cut my hair - I looked like a crazy hamster, Ray & Molly, Nicky & her Hubby (whose name I forget). Best wishes to you all.
Great time spent there, happy daze.

 

[Channa]

My take on this is you are respectfully looking to cure a problem that doesn't exist.

12v in a lot of cases attempts to maintain refrigeration but doesn't refrigerate in the true sense...results differ van to van and that is exemplified by ambient temps outside

Re gas and safari rooms potentially an issue to consider but the air volume in the safari room ensures flue gasses aren't a problem as in the main well ventilated with draughts ... not withstanding correctly serviced and an exhaust analyser used periodically to double check adds a bit of belt and braces approach

As already suggested gas is the sensible option rather than 12v and foing pure 240 using batteries considering weights and loads seems far more complicated remedy to achieve the same result

Channa

 

[Deleted member 62288]

to summarise

I am very grateful for all of the responses and suggestions.

There have been many interesting discussions.

I have just completed the upgrade of the 12v battery bank to 460Ah victrons, fed by 340 watts of panels.
I have by-passed the ebl, so it is unaware of this charging source so it will only see charging from the alternator or the ehu.

I already know the fridge performance when using both LPG and EHU in a wide range of climate conditions.

I am now exploring my new wealth of 12v reserve power, I want to understand what it's limits are, now is a good time to do it as it's been really sunny here for the last week or so with more to come, This gives me plenty of free solar power to play with.

So my question is how does the fridge and batteries perform when operated on 12v permanently.

From the results I can then understand my options as I encounter different situations as I travel.

A supplementary question has arisen, that of how do I locate the existing circuitry to enable me to plug 12v into the cable loom as there seems to be all kinds of relays and switching that I have yet to get my head around.

My objective would to be to install a change-over switch that facilitates normal operation eg 3 way gas/12v/220v with the added option of switching the load off the EBL and onto the leisure batteries.

So realistically, LPG is not in the equation.

#thanks, james

 

[Byronic]

I'm not disagreeing with you, your set up is similar to mine.

My current topic is how do I run my fridge on 12v permanently ?

so how do you run your fridge ? on LPG.

That doesn't answer my question.

You've answered your own question, with plenty of batteries and solar.
Not necessarily my preferred solution.

How do I run my fridge? Very infrequently, we're vegetarians of a
kind. Shop often, luckily missus enjoys shops. Gas usage for fridge
negligible. Use plenty of gas for heating, save ourselves before the
planet, you could say.

 

[Nabsim]

Not had any luck finding an English version so far sorry. I may be wrong but I believe that more than just my EBL will pass power out for a fridge, (does your EBL still have the power out and fuse for fridge?) and only requires the fridge to be turned on for this to happen. I have to manually turn the leisure battery bank on and off but once fridge is turned on it stays on no matter if its from starter or leisure battery. I think it may be worth you sending an email to Martin at A and N Caravan Services, they are very knowledgeable when it comes to Schaudt kit and he may be able to point yo in the right direction he has been very helpful when I have had any questions.

I dont think the 3 way fridge is the right option for your 12v set up if what I have read about them is correct but I understand you want to give it a try and see if it will work.

You can contact Martin using the page here: A and N Caravan : Caravan and Motorhome Servicing/repairs, Habitation checks.

 

[Nabsim]

Just having a look at the manual for my EBL 100-2 and it mentions two relays in the EBL for fridge, one is for absorber fridge (your 3 way) and the other is for AES/compressor fridge (my Waeco) and the output connectors are block 2 and block 3. Is it as simple as seeing which of these two blocks your fridge connects to and using the other?

 

[Deleted member 62288]

I'm lowering this requirement as a low priority for now, the issue is holding up my progress with the other upgrades and re-wires.

There is some relay/switching alchemy happening that I cannot figure at this point in time.

The fridge itself will happily run on 12v, it is rated at 150Watts (ish) so the batteries will manage the load easily.
How well the 12v constantly on will handle the cooling is still an unknown. Other members have suggested that this is an issue, with one comment about it not ending well.

If the fridge is designed to be 3way with explicit 12v running as a design-in option, HTF can this "not end well?"

But Hymer wired and configured the 3x way switching to disable 12v running unless the engine is running, I am looking for a method of defeating this limitation and optionally switching it in or out.

The challenge that I have to meet is to understand where the switching is happening, eg at the EBL or somewhere else.

I can't access the wiring and control box at the back of the fridge unless I slide the entire fridge out into the cabin area.
So, for now, I must be getting on with the seat/locker re-works then onto the dashboard / cab area.

I bought a switch-panel from Wildebus that I want to see installed on the dash for the various after market toys and kit that adorn the divers area.


Thanks again for everybody’s input, comments and suggestions,
keep 'em coming.

james

 

[Nabsim]

Block 2 and block 3 are on the EBL not the fridge end, did you check which you have connected?

 

[Deleted member 62288]

Block 2 and block 3 are on the EBL not the fridge end, did you check which you have connected?

Yes, Mine is block 1, pin 2 yellow (relay trigger I think) pin 3 Brown (-ve) pin 4 Blue (+ve).

Block 3 is the data connection to the DT 200 display, and I think that block 2 are inputs not outputs, but I may be wrong.

The EBL switches the 12v off unless the engine is running (or so I thought), but I see the battery voltage (nom 12v) in all cases, on pins 3 & 4, whether the engine on or off, EHU in or out, also the fridge has 12v always, to handle the lights and control board so the yellow wire has something to do with it, at the fridge end, probably inside inaccessable fridge control box, on the back of the fridge.

I will try to trigger the relay via Block 1, Pin 2 by applying 12v, but only after more research, I can do without a knackered EBL, at this or any point in time. But as DelBoy says, He Who Dares, Wins.

I suspect that the yellow wire triggers a relay fixed to the back of the fridge.

But I am unclear yet on the logic of the switching.

 

[Nabsim]

Yes same here, I think the D+ is the trigger from the switch but I don’t have enough paperwork to track it properly. Have you asked here, they are very knowledgeable when it comes to EBL’s A and N Caravan : Caravan and Motorhome Servicing/repairs, Habitation checks.

 

[Deleted member 62288]

found an English PDF

Yes same here, I think the D+ is the trigger from the switch but I don’t have enough paperwork to track it properly. Have you asked here, they are very knowledgeable when it comes to EBL’s A and N Caravan : Caravan and Motorhome Servicing/repairs, Habitation checks.

I've not yet managed to locate an English PDF for the EBL 100 B/911.502, I only have a German version.

But I now have an English version for the EBL 100-2/911.503, which looks the same as above.
The 2 versions use different circuit boards, but the external wiring seems to be the same for both.

Now I can begin to see what the relay logic is doing.

Part of the puzzle is that the EBL Block 1 is wired as per an AES/Komp fridge on pins 3 & 4 whereas the circuit diagram shows Pins 1 & 3 should be used for an absorption fridge, but my pin 1 is empty.

Perhaps the original fridge has been replaced - I have no idea.

However this is now a low priority as I need/want to get loads of other stuff done.

If this website has a members upload area, I can upload the PDF there, but I believe this is not available.

If you want a copy, email me via the members message area with an email address and I'll send it to you as an attachment.

james