Checkout this Awesome Fridge

[condor22]

So, I'm back from a 3 weeker to the GT and here are some details re fridges.

My caravan has a 129lt Thetford N404 3 way fridge. I precooled it on 240VAC before leaving for the trip and it was set to about 2 deg C. The weather on the trip over was coolish at just under 20C and I checked the fridge a couple of times enroute. I also did an overnight stop at Nhill as I didn't leave Adelaide until 4pm and put the fridge on LPG whilst stopped. Next morning back to 12VDC and drove to my camp spot and returned the fridge to LPG for the next week. During that time the fridge hovered between 1.2C and 3.8C and included a couple of 30C days. I then went to a van park for the remainder of the trip and the fridge was on 240VAC. However......

The day I came home was a 36C day, I left Vic before noon and got home around 7pm. When I left the van park the fridge was at 3C, I next checked it at Horsham and it was now reading 6C. By the time I got to Nhill it was up to 9.6C. Here, I got my multimeter out and checked the voltage at the fridge terminals, engine running and fridge on, it read 12.6V. This tells me that when driving on a hot day the fridge is not working well even though I'm getting a good voltage at the fridge.

As I was near the end of the trip, there was not a lot in the fridge and nothing in the freezer section, (except 5 eski ice blocks, still frozen) so I transferred the food and drink to the Engel in the 4x4. I don't normally detect in the warmer weather, or in fact use the van either. Conclusion - Fridge is good on 240VAC, good on LPG and anything over 25C ambient, crap on 12VDC. When I got home the an fridge was up near 12C.

Due to my flattening the 4x4 Aux, I only used the Engel when needed, i.e. shopping or a party I attended as the battery is not real good. But it worked flawlessly even on the 36C day, holding 2-3 C the whole time. (I was driving 600kms so the Redarc kept the battery up).

If I wanted to use the van in hot weather when on 12V, I would not trust the Thetford, but changing over to a compressor fridge ($1,500 to $2,000) would also require doubling the battery bank and solar to run it (probably another $1,500). and, That would then mean a bigger solar controller and 240VAC charger another added expense. I'm sure SWMBO would not approve of the expense,

 

[condor22]

I might add, this trip, I left the Honda at home, so during the week I camped, I relied solely on the solar and battery for van power, charging phones and detector batteries. The system worked great and solar filled the batteries everyday.

On one of these days the temp was about 34C, I sat in the van with the Sirocco fan going, TV and Laptop running most of the day (afternoon and evening) and the solar still filled what I'd used the previous night as well as coped with what I was running.

As I had no genny, I used LPG to heat water for a shower every 2nd day, all cooking on the LPG stove as well as the fridge use. I got 6 days out of one 4.5kg LPG bottle, which is about half what I get when I use the genny to heat the water and the M/wave to cook.

My conclusion here is, take the genny, the pros far outweigh the cons

 

[Ridge Runner]

Well that's not too good mate Ay ??

I wonder why it is behaving like that, normally they are pretty good, But I do think the compressor fridge is the way to go.

 

[condor22]

Well the fridge works on the other 2 power sources. The 240V element is bigger than the 12V one (watts wise). My previous van was a 3 way and Dometic, similar situation.

First van was a 12V compressor fridge, Vitrifigo, no issues re temp, but a smaller fridge. Plus I only had 1 x 64W panel driving 2 x 100AH batteries, not really set up for extended bush stays. At the time it was all I could manage, so I've had both 3 way and comp fridges in a van and know which I prefer

 

[Ridge Runner]

Well I hope good luck comes your way this time, It's start to wear you down throwing money at things over and over,

Good luck mate, :Y:

 

[Ridge Runner]

I just ran the 47L for 73hrs 42mins / 3 days+ and it is still over 60% charged 32.166Ah and 382.7w, The limit on the Battery 30% SOC according to the Specs, So I'm pretty happy with that.

 

[BigWave]

My Van fridge does the same on 12V - a Dometic.
On 240Vac and gas it is fine, but on 12V (from the car), it warms up a little (say from 2 to around 7C under 30C daytime).
I was told this from the start, so knew what to expect - that's just their nature.

 

[Nightjar]

Mentioned details on another post about our problems when long distance travel with the van and 3 way running on 12V.
Definitely solved our problem by increasing cable gauge from ute to van. As Condor mentioned we always pull our fridges down with the grid 240V before trips. Now 500km and 3 way fridge remains stable around 2-3C. Prior to mod, within 200km's temp would climb to 7-8C.

 

[Tathradj]

When I wired my Prado, I used
8 square through a Heavy Duty
Multi Pin connector right to the van.
I still have to get rid of the " excuse "
wiring used on a short run to the fridge
but my 3 way Dometic Fridge stays cold
on a long trip.
And starts to freeze up in the freezer section.

I replaced the 12v element when the 240v one
went as over time, Elements lose their effectiveness.

Food poisoning is not a nice thing. :awful:

 

[LONEWOLF]

Yes not nice when you are out Camping and away from the comfort of Your Toilet ...

LW....

 

[condor22]

Re my 3 way fridge - I checked the manual and it states that to operate effectively on 12VDC the voltage needs to be a minimum of 11.7V.

So my 4x4 consistently reads 14.5V on the dashboard, which is the start battery voltage. I've measured the voltage with the engine and fridge both on at the 4x4 battery, the Anderson at the rear of the car and at the fridge terminals behind the fridge. There is a gradual voltage drop throughout. I guestimate the return cable length at approx 16M.

When the van was wired OEM through the power supply/distribution device, the voltage at the fridge had reduced to 11.9V which is still above the stated minimum. In this configuration, not only was the fridge operating, the power supply was also charging the van battery, so an added load.

I disconnected the Anderson input to the charger and also the fridge wires and connected them directly together, cutting the charger out of the system. So the only power used from vehicle is the 3 way Thetford. By doing this the voltage at the fridge is now up at 12.9V, which is effectively the voltage I would get from a fully charged good condition AGM, therefore nominally the ideal voltage. I can charge the van from solar when driving, so disconnecting the charger was not an issue.

As we know, the hotter a system gets, the resistance also increases, which is probably why I got a reading of 12.6V on the hot day I traveled. But still a good voltage. As I mentioned I had 5 frozen ice blocks in the freezer to give some bulk in the freezer. The fridge section was approx 25% full, mainly drinks. I also noted that the fridge VDC has a maximum of 15.4 V. So I'm wondering if increasing the voltage will make any improvement as the first place to achieve this is upping the wiring gauge.

There's not a lot of info I've been able to find re this on Google. I'm also of the belief that the 12 V fridge element won't produce any more power by increasing the voltage, all that would do is reduce the amperage if it's already at maximum. So little to gain. I should also mention I only opened the fridge once at lunchtime for less than 10 seconds.

Other than the obvious "go buy a compressor fridge" or "travel when it's cooler" any thoughts would be welcome........

and for Ridge Runner - No I escaped, oops, emigrated to Oz over 50 years ago and aint going back

 

[bicter]

The 12V system on the 3 way isn't really designed to cool things down, more maintain temperature while traveling. Pretty sure you knew that anyway

If you need to run the fridge longer term on 12V out bush, have you considered using an inverter to run it from the 240V element. Will probably chew a bit more current.

It may also be worth considering Tathradjs comment: "replaced the 12v element when the 240v one
went as over time, Elements lose their effectiveness."

Cant recall which vehicle you have.... it wouldn't have a smart alternator on it would it? If so, that could be the problem.

 

[condor22]

No it's not a smart alternator

Yes I know 12V is only "supposed" to maintain

I run on LPG when in the bush, this occurred when travelling....

 

[Ridge Runner]

and for Ridge Runner - No I escaped, oops, emigrated to Oz over 50 years ago and aint going back

I can believe that, The Guards here always leave the Gate unlocked, :lol: :lol: :lol: :lol: :lol:

I hear 50 years ago one of them got a Knighthood :trophy: layful: :lol: :lol: :lol:

 

[Tathradj]

the 12v element draws around 10 amps to run. I based my theory on amps, not volts.
I have around 12.5 volts at the fridge connector.

The trailer plug/socket I use is a Narva Multi Pin.
The large pins are rated to 50amps but I would not like to test that one on a long drive.
I am drawing up to 15 amps through the connector.

 

[condor22]

and for Ridge Runner - No I escaped, oops, emigrated to Oz over 50 years ago and aint going back

I can believe that, The Guards here always leave the Gate unlocked, :lol: :lol: :lol: :lol: :lol:

I hear 50 years ago one of them got a Knighthood :trophy: layful: :lol: :lol: :lol:

Not nice RR.... My Sis lives in the UK, she is also an Oz citizen and with the Brexit debacle, sometimes wishes she was here.

 

[condor22]

Tath, don't know if I ever mentioned this.....

My Trailer hitch is a standard flat 7 pin plug. It was originally wired with a 5 pin harness by Holden, the Electric Brakes were added by an Auto Sparky to that connector. Most OEM vehicle looms are a 5 wire harness as the brakes/fridge is not normally included from what I was told, both by Holden and my previous Tojo ride.

However the van fridge power (same sparky) is via an Anderson plug with separate HD wiring. I have mentioned that under the hood a 70A cont solenoid, IGN switched powers the extras.

It has 2 HD cables going from it, one to the van fridge Anderson, the other into the rear of the wagon to power the Redarc charger for the AUX battery. The sparky originally put a 30A self reset circuit breaker on each run under the hood, I'm not a big fan of them, so I replaced them with 2 x 30A HD fuses. The issue with the breakers is that when they get hot i.e. a fault like a short, they trip. But when they reset, they reconnect the fault and hopefully trip again. Theoretically they could keep doing this and possibly damage something else connected to the circuit. The fuse is better as once it blows it does not reconnect and allows for fault finding before replacing it.

So the only thing the 7 pin feeds are van external lights and brakes. The only reason I chose the Anderson connector at the time is that the van came with a separate Anderson fridge feed, which I believe is the best way to go as it negates the issue of trailer plug pins not being heavy enough.

 

[Ridge Runner]

and for Ridge Runner - No I escaped, oops, emigrated to Oz over 50 years ago and aint going back

I can believe that, The Guards here always leave the Gate unlocked, :lol: :lol: :lol: :lol: :lol:

I hear 50 years ago one of them got a Knighthood :trophy: layful: :lol: :lol: :lol:

Not nice RR.... My Sis lives in the UK, she is also an Oz citizen and with the Brexit debacle, sometimes wishes she was here.

Group Hug, O

You know I didn't mean it, :Y:

I understand how she feels, For the first time in my life since my early 20's I have stopped watching the News,

 

[condor22]

Hey, I'm a POM taking the P*** out of an Aussie, living as a POM, aah revenge is sweet, lol......

 

[Ridge Runner]

Hey, I'm a POM taking the P*** out of an Aussie, living as a POM, aah revenge is sweet, lol......

I been here too long now I sound like a POM a lot of the time unless I hurt my self then my Cussing is pure Tru Blue, Or if I am clowning about,

Hey we can tell every one we are exchange students, LOL :lol: :lol: layful: layful: layful: