Ways to run a 3 way fridge.

Gonefishing1955 · Member

Ways to run a 3 way fridge.

67HR · Senior Member

Hi Chris, I got my van about 20 months ago, when I purchased it I followed the info from the auto sparky in this clip. https://youtu.be/iQsYPVydWmY?si=Brtb2-hBLN17O7BS

I've had no issues since following the guys advice.

Cheers Trev

Peter_n_Margaret · Senior Member

With the low cost of solar why would anyone plan for a 3 way fridge?
You would never tolerate one at home.
Cheers,
Peter

Whenarewethere · Guru

Maybe there is time to get it replaced with a compressor fridge so you don't have any expensive consumables for the rest of its life.

Also a compressor fridge will work on pretty much any angle.

Gonefishing1955 · Member

Thanks that was interesting info, will need to watch again to take it all in. Guess a motion switch in the red line will solve the draining of power issue if that was a concern.

Cheers

Chris

Radar · Guru

We run our 3 way, 180 litre via the lithium caravan battery.

Living in the sunny state we rely on our solar to keep the battery in check 24/7.

Previous when we had AGM battery we did via Anderson plug connect to the car to help maintain the battery but now that wiring is for emergency purposes only.

Best advice I have been given is to keep it as simple and our 3 way has worked this way for over 8 years now wired to the house battery for when on the move.

As for replacing the refrigerator, I am a bit old fashioned there, what not broken, can't be fixed then maybe go the other path of 12 volt.

TimTim · Guru

Hi Chris,

Firstly welcome to the forum.

Caravan manufacturers generally provide an information sheet on what the wiring requirements are for your tug so as to match up with the van. I would ask them for that first.

Generally you have the 12pin plug, grey Anderson to provide to provide power (in my case to a Redarc Manager 30) and a red Anderson plug for the ALKO escape. You may have different components in your van where as I have an all in one stystem.

https://www.supremecaravans.com.au/upload/files/Wiring%20Diagram%20for%20Towing%2022_12_21.pdf

Here is a wiring diagram and I had to simply do the loop from 11 to 12. You could of course wire directly to your batteries but surely they have done the wiring beforehand.

The quote to upgrade your Anderson plug, even if it does need doing, sounds way over the top and I suspect you probably have adequate cable size anyway. i was quoted $1000s so I simply did it myself and rather than run the cabling through the firewall and back out the other end I simply ran the cables for the two Anderson plugs along the chassis. Less that $200 in components. What cable side is the wire to your Anderson plug?

Good luck

Tim

-- Edited by TimTim on Saturday 7th of September 2024 01:45:54 PM

Gonefishing1955 · Member

Hi Timtim, not sure about the wire size in my existing anderson plug, but was adequate to charge my 200 ah lithium via an viktron dcdc charger. The dealer is fitting this in my new van as I removed from the old one. I am likely to run my own red plug it does not seem that hard.

Gonefishing1955 · Member

Hi again, Timtim. Just had another look at your wiring diagram , where does your fridge draw its power from the house battery ?.

TimTim · Guru

Hi Chris,

Fridge is connected to house batteries as per the diagram below but it needs 12V charging from the tug to operate.

Ask for the make and model of the fridge and look online for the installation manual.

Tim

-- Edited by TimTim on Saturday 7th of September 2024 06:43:54 PM

Gonefishing1955 · Member

Hi Tim,

Our fridge is same as yours, so apart from perhaps some inefficiencies I can see no reason why you could not run Manually on a 1000 watt 240 v inverter. If the house battery can cope and is being charged from the car.

I am starting to think the AES system is not the big deal I first thought. Looks to me like you have to intervene at every stage anyway, turning gas on / off. Pluging in mains, removing mains and then for peace of mind checking that the bloody thing is working when you rely on 12v.

Again appreciate your comments.

Cheers

Chris

TimTim · Guru

Hi Chris,

If your fridge is the same as mine you can set it on auto to select which power source to use first. It automatically checks for 240V, 12v and then gas so there is no need to change anything. The power draw is about 21A from battery but Im unsure how long the cycle is so if you select manually then you dont want to walk away and forget to change over. It does have an alarm to warn you though if the power source is set on manual and the power source is cut. I suppose it becomes natural to check when you set up or leave camp along with all the other checks like windows closed, water off etc.

I have not had any issues running on 12V so havent considered the need to run it on 240V through an inverter even though I have 760Ah of LiFePO4.

Good luck

Tim

Big Mal · Senior Member

Some places just make it complicated and expensive .................. I run a 7 pin which is just for the van lighting brakes/clearance etc the fridge has its own decent bit of wiring, an 8 B&S cable from tug battery pick up to van fridge, anderson junction on draw bar and I fitted an anderson at the fridge end as it makes a very good step down from the 8 B&S size to the fridge cabling, the D+ wire, which shows the fridge that its hooked up to 12v is just tapped into the fridge anderson, on the fridge wiring side is added a Fridge Switch which shuts off the 12v when stationery so cranking battery isn't deaded.... i don't run any charging system from tug to van as my solar does the job, i look at things being if you need to charge while driving down the road how will it managed parked beside a creek for a few weeks................

Old 3 way was just 12 when it needed to be replaced last year, I went for another 3 way as a compressor job meant i would have to add some more storage to cover it and the fridge was costing enough as it was, not a great variation in cost between the 2 but extra battery bumped it up lot ............. I have found the biggest problem with 3 ways is very poor installation, brand means nothing they all seem to just chuck them in a hole with little care so long as it works ...

Gonefishing1955 · Member

Thanks Mal, will probably do the same with my D+ wire, add a switch like you.

Cheers

Dick0 · Guru

Big Mal wrote:
Some places just make it complicated and expensive .................. I run a 7 pin which is just for the van lighting brakes/clearance etc the fridge has its own decent bit of wiring, an 8 B&S cable from tug battery pick up to van fridge, anderson junction on draw bar and I fitted an anderson at the fridge end as it makes a very good step down from the 8 B&S size to the fridge cabling, the D+ wire, which shows the fridge that its hooked up to 12v is just tapped into the fridge anderson, on the fridge wiring side is added a Fridge Switch which shuts off the 12v when stationery so cranking battery isn't deaded.... i don't run any charging system from tug to van as my solar does the job, i look at things being if you need to charge while driving down the road how will it managed parked beside a creek for a few weeks................

Old 3 way was just 12 when it needed to be replaced last year, I went for another 3 way as a compressor job meant i would have to add some more storage to cover it and the fridge was costing enough as it was, not a great variation in cost between the 2 but extra battery bumped it up lot ............. I have found the biggest problem with 3 ways is very poor installation, brand means nothing they all seem to just chuck them in a hole with little care so long as it works ...

A 100A ignition relay together with a fuse relay is the surest to disconnect from Tug cranking battery. That should have been fitted in the first instance. Seems like DIY wiring was done. The relays can still be fitted in engine bay for peace of mind. Adding a VSR is even better as it will ensure the Tug cranking battery is charged before powering the Den.

Dtassie · Veteran Member

I recently asked a mate what fridge he was running in his caravan, he said a 3 way running on gas only.
I said yeah when your parked up, he said no all the time!
Crickey how are you still alive, he said he shuts gas off before and after filling his vehicle. LOL

watsea · Guru

Dtassie wrote:
I recently asked a mate what fridge he was running in his caravan, he said a 3 way running on gas only.
I said yeah when your parked up, he said no all the time!
Crickey how are you still alive, he said he shuts gas off before and after filling his vehicle. LOL

Maybe you could ask your mate, what happens if his van gets mixed up in bingle that is strong enough to break a gas line that is still connected to the open valve of his gas bottle? Caravans often get well smashed up in an accident.

Risk: low likelihood but high consequence.

-- Edited by watsea on Sunday 22nd of September 2024 11:07:52 AM

67HR · Senior Member

Dtassie wrote:
I recently asked a mate what fridge he was running in his caravan, he said a 3 way running on gas only.
I said yeah when your parked up, he said no all the time!
Crickey how are you still alive, he said he shuts gas off before and after filling his vehicle. LOL

I think we all may be guilty of forgetting to turn a bottle off at some time, but to consciously travel not only with the valve on but fridge running is diabolical!