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Timbo
23rd November 2010, 01:52 PM
All right you lot, I have some questions for those of you who have FRIDGES in your 4WD's!

They are too expensive for me to buy right now, and I'm going to be pulling apart my home made drawers and re-designing them first.

I dont understand the fridge/freezer. Every time I look and the Engel/Waco fridge freezers, I can work out which part freezes and which part is just the fridge?

I would have expected when the lid shut, it would seal off 2 sections, but they dont. Every one I have seen in the shops, the whole thing is frozen inside which leads me to believe one of two things.

1. Fridge/Freezer means it's a Fridge, OR, a freezer.. not both at the same time.
2. You can some how control 2 halves separately.
3. I'm crazy

Now I'm leaning towards option 1. but it doesn't make sense to me. What if I have meat or something else I want frozen, but also have goods that I just want cold, like cans. How do you do both?

Also, all of you blokes that have fridges..

What size is your fridge?
How many people did you buy it for? ie: Just you? Your family and if so, how many?
Which brand do you have? Why?

macca
23rd November 2010, 06:54 PM
Mate that is a loaded question or series of them. Fridges are a discussion held around many fires, what a person has in their 4b is invariably the best thing on the market.

For me its a 40ltr Engel, had a 39ltr since 1982 and upgraded in 2006 to the more modern unit that used less power.

Been used as extra fridges at home as well as many trips away. I cannot fault them and have just bought another for my 80 year old Dad who is doing up a commuter bus for touring.

I've seen many fail or play up on trips which is a real PITA, but never an Engel. Most of my mates have Engels so we dont have trouble carrying food etc for others whose fridge has stopped working.

Our 40 has been plenty big enough for 2 people, we cryovac stuff at home and allways get the butcher to do that as well. Room enough for enough beers to keep me happy as well.

I think those double section fridges have 1 for freezing and the other as a fridge, the single section units are able to be used as 1 or the other not both at the same time.

They are a good investment, and buying quality today means you will get years of great service from it.

Good luck

Macca

AB
23rd November 2010, 07:57 PM
Great replies guys thanks!!!

If anyone didnt know Timbo and I work together, infact I'm Timbos Boss so he's one lucky bugger to have a boss like me...haha

We went out today to get some maps on the Toolangi area and saw about 40 different fridges and started asking the question's which none of us could answer.

I've only owned a very old school but reliable trailblaster (1980's fishing trawler fridge) weighs 70kg's and only holds a small amount so we were very intruiged to what other's here have to say about what their own set up these days.

p.s Tim, I only hired you because you turned up in a Patrol to your job interview...lol

Woof
23rd November 2010, 09:15 PM
I've got a 60l Engel Fridge/Freezer on a drop down fridge slider, the freezer compartment has a lid so I just put all of the pre frozen stuff in there and Bob's your uncle, as Macca said cryovac the meat (I get my butcher to do that).
Everything else goes into the fridge compartment, beer, eggs, beer, milk, beer, butter, beer, tomatoes and of course beer.
The thing I like about the combination of the fridge/freezer is you can always put the beer in the freezer for a while to bring the temperature down, just don't forget it.

Woof
23rd November 2010, 09:30 PM
Forgot to add, always pre chill the stuff that you are going to put into the fridge and have the fridge going the night before you are going to put stuff into it.

Timbo
23rd November 2010, 10:50 PM
Great tips guys, has answered a few of my questions indeed.

I'm not trying to spark a brand name debate.. that could go on forever like the Patrol vs Landcruiser argument (Patrols are better, Landcruisers have a better rear door :P ) but I would certainly do my research into the components between the 2 brands and the warranties.

My ex GF's Mum's partner.. (lol mouthful) had a couple of big Waco's and i think an Engel. Mainly used for fishing and 4WD'ing but sometimes as a back up for home. They are both great units.

So much to buy, so little money.

AB, you need to pay me more.

Woof
23rd November 2010, 10:53 PM
So much to buy, so little money.

AB, you need to pay me more.
Yeah come on AB, you just cut my overtime down so surely you can pay Timbo a bit more.....lololol

AB
24th November 2010, 07:46 AM
Yeah come on AB, you just cut my overtime down so surely you can pay Timbo a bit more.....lololol

$2.50 per hour is more then enough Timbo...lol

Timbo
24th November 2010, 08:08 AM
hahah.

I also had another question.

How many volts do those fridges drain? How long do they last on a battery not being charged? I imagine you'd really have to go for a drive every day or second day to keep the battery charged up from the excessive drain.

macca
24th November 2010, 01:27 PM
This get a bit harder to understand, volts are not a great issue... except they indicate the state of charge (SOC).
Amps is the power that runs your fridge in this case, a battery with more amp hours (Ah) lasts longer

Example using a 100Ah battery, this is hyperthetical as efficiency of the battery is not that good.
100amps for 1 hour and its dead flat
50amps for 2 hours
10amps for 10 hours and it goes on

If your fridge runs at 2.5amps it should run for 40 hours.... but

1) The fridge generally cycles on and off so will last longer.... but

2) Batteries dont like running to dead flat and my LifelineAGM (Adsorbrd Glass Mat) are recomended to run no lower that 50% SOC so the 100Ah now has only 50Ah available. The reason for this is number of recharge cycles, run to 0% SOC and you will get a couple of hundred recharges. Run to 50% or higher and the recharge count goes up dramatically (50% = 2000 cycles)

What that effectively means is you buy a battery twice the size you think you need.

All this gets worse because a car dual battery charging system will often not charge above 80% unless you reach for the credit card. Now you have effectively 30Ah to run the fridge, camp lights etc.

30Ah will run a fridge set on freeze for 24 hours no worries and AGM batteries take a higher current charge so charge faster giving more usable energy in a short time running the engine.

Lifelines SOC open circuit voltages. 100% = 12.80v, 75% = 12.55v, 50% = 12.20v, 25% = 11.75v and 0% - 10.50v.

Gives you a bit of an idea without confusing I hope

Macca

TimE
24th November 2010, 01:30 PM
hahah.

I also had another question.

How many volts do those fridges drain? How long do they last on a battery not being charged? I imagine you'd really have to go for a drive every day or second day to keep the battery charged up from the excessive drain.

How long is a piece of string?

Amp hours rather than volts is the issue.

I work on the following set of assumptions;

I have a Waeco 50l, that cycles on for around 1/3 of 24 hours (assume a day time temp max in the mid 20s) and draws around 3 amps per hour, so that is around 24 amps per day.

I have a 105 amp hour AGM aux battery that is put on the charger (CTEK 7000) to ensure that it is fully charged before each trip. The battery will discharge down to 10.4 volts max (setting on my fridge will automatically turn the fridge off at 10.4V). So lets assume that at the best I can get is 70% of the available amps out of my battery before it is too flat to run the fridge, say 73 amps.

Simple sums (70% of 105 amps = 73.5 amps available, divided by 24 amps draw per day) tell me therefore I should expect around 3 days of uncharged usage from the battery. I have actually gotten 4 days out of a battery without it going flat, the day time temp max being around 22 degrees.

Things that will affect these assumptions are day and night time temps, how full the fridge is (the more already cold stuff in it the better), how the fridge is packed, always put things in the fridge pre frozen or fridge cold. I always fill my fridge the night before a trip with already cold food and drinks and run it on the charger overnight prior to setting off.

My golden rule for using the fridge is never open it unless you really have to, be quick to grab what you need and never ever ever ever ever ever let kids near it!

Quality cabling and connectors are also a must, e.g. the cig plug on my Waeco power lead was turfed and replaced by a 50 amp Anderson plug.

Timbo
24th November 2010, 01:36 PM
Solid answers guys. It shows that there is a lot more to it than plugging it into the ciggy lighter.

I think when the time comes, I'm going to get professional advice about what I need and hopefully I don't get ripped off.

macca
24th November 2010, 01:39 PM
How long is a piece of string?

Things that will affect these assumptions are day and night time temps, how full the fridge is (the more already cold stuff in it the better), how the fridge is packed, always put things in the fridge pre frozen or fridge cold. I always fill my fridge the night before a trip with already cold food and drinks and run it on the charger overnight prior to setting off.

My golden rule for using the fridge is never open it unless you really have to, be quick to grab what you need and never ever ever ever ever ever let kids near it!

Quality cabling and connectors are also a must, e.g. the cig plug on my Waeco power lead was turfed and replaced by a 50 amp Anderson plug.

TimE is right on the money there, another tip for efficiency is to repack after preparing lunch or whatever before you eat as the stuff on the table is warming up and needs to be cooled again. Power to the fridge is vital, better amps at the unit itself the better it wii run.
Macca

sweet_gq
29th November 2010, 02:01 PM
another tough question... how big is your battery, how many batteries do you have.

Big difference between waeco and engel is waeco has battery protection, this means that once your battery drains below 10.4v (i think that is the low protection) you fridge will turn off.

I have two waeco's, a CDF35 in the back and a CDF11 in between the kids seat in the car. I also have a 65w solar panel on the roof to assist when base camping.

I have about 150amp hours in second and third battery.

I just got back from a weekend, set up camp on fri night, left yesterday at lunch. Batteries and solar ran big waeco as a fridge and little waeco as a freezer all weekend without starting car.

most fridges will cycle about 2-3 amps per hour. a lot of things though, on a 40' day, they could cycle 5-6 amps per hour.

sorry there is no clear answer but i hope it helps a bit

B

Timbo
29th November 2010, 02:21 PM
Thanks for the input mate, good to hear different perspectives.

macca
29th November 2010, 03:53 PM
40ltr Engels run at 0.5 - 2.5 amps, run flat out for an hour it will only use 2.5Ah not 5 or 6, Waecos site says they run at an average of about 0.87 amps 5deg in fridge and 32deg ambient so no idea what the maximum current might be.
There are lots of good fridges on the market but if they draw a lot of amps they might not be worth considering if battery life is important.
Owners of the different fridges might be able to post run amps so you get an idea of what power they use.
Macca

Bigcol
2nd December 2010, 01:22 AM
What size is your fridge?
I have a 40L Engel & a 27L Engel
- I got the 27L because the 60L that I had was way to big when we were away camping, and I wanted something smaller.
then I realised that the 27L was a wee bit tooooo small for our needs, so I sold the 60L to my nephew, and brought a new 40L
now Im happy as.... if we are going away for a weekender, the 27L does the job, if longer than 3 days, the 40L gets packed
as has been said already, I run both fridges the night before on freeze (240V), then pack them early, then plug into 12V then away
ALSO
I have a 60L in my Jayco, so they are mainly only for drinks and lunch goodies, main food is in the camper

How many people did you buy it for? ie: Just you? Your family and if so, how many?
well, there is my wife, my daughter and myself
Which brand do you have? Why?
this one is a harder choice for all
in my case, I asked about 20 or so truckies that I know & come to my work (middle Great Sandy Desert)
what do YOU have and use, and WHY?
only 3 had Waeco's and 1 offered it to me for free, as it kept breaking down, another wanted rid of his for the same reason - something about the "Thermal Overload Fuse"
the rest with the Engels, said they never had a problem with them - that swung the deal for me
plus a mate of mine brought one new in 1981 - and its still going strong (I remember him buying it the day I met my future Missus - but thats another story)
I had my 2nd hand 60L for about 3 years, and Ive had the 27L (2nd hand as well) and 40L(new) for about the same time

they are ALL expensive, but if you look after them, they will ALL last a long time

as I said, MY choice was the Engel

cheers

Timbo
7th December 2010, 11:05 AM
What size is your fridge?
I have a 40L Engel & a 27L Engel
- I got the 27L because the 60L that I had was way to big when we were away camping, and I wanted something smaller.
then I realised that the 27L was a wee bit tooooo small for our needs, so I sold the 60L to my nephew, and brought a new 40L
now Im happy as.... if we are going away for a weekender, the 27L does the job, if longer than 3 days, the 40L gets packed
as has been said already, I run both fridges the night before on freeze (240V), then pack them early, then plug into 12V then away
ALSO
I have a 60L in my Jayco, so they are mainly only for drinks and lunch goodies, main food is in the camper

How many people did you buy it for? ie: Just you? Your family and if so, how many?
well, there is my wife, my daughter and myself
Which brand do you have? Why?
this one is a harder choice for all
in my case, I asked about 20 or so truckies that I know & come to my work (middle Great Sandy Desert)
what do YOU have and use, and WHY?
only 3 had Waeco's and 1 offered it to me for free, as it kept breaking down, another wanted rid of his for the same reason - something about the "Thermal Overload Fuse"
the rest with the Engels, said they never had a problem with them - that swung the deal for me
plus a mate of mine brought one new in 1981 - and its still going strong (I remember him buying it the day I met my future Missus - but thats another story)
I had my 2nd hand 60L for about 3 years, and Ive had the 27L (2nd hand as well) and 40L(new) for about the same time

they are ALL expensive, but if you look after them, they will ALL last a long time

as I said, MY choice was the Engel

cheers

Thanks for taking the time to give some first hand experience Col.

Cheers!

tkn
7th December 2010, 02:07 PM
Timbo,
Without wanting to repeat what has been said, most of which is spot on. Beware seeking "professional" advice, in my experience most "professionals" have an economic interest associated with their advice. What macca and others have suggested is that with 12VDC fridges Engel has been and probably still the yardstick by which all others are measured. I don't own an Engel (didn't like the top opening) but built a cabinet to house a Dometic (now owns Waeco) caravan fridge (didn't like the Engel swing door fridge, which sacrificed a deal of space to accommodate the compressor) and that has had a pretty hard life over the past 5 years and is still going. A top opening fridge has the disadvantage that you can't stack anything on top of it if you want easy access - drop slides have now made that situation better. Caravan fridges (even as little as 35 litres) have a separate freezer compartment (will make ice blocks, but no good for icecream) and there are some 2 door models.
Insulation and cross flow ventilation are essential for efficient fridge operation, no matter which brand. If you are rejigging your Patrol, try and keep the fridge out of direct sunlight i.e. heat and as low in the vehicle as possible (heat rises). Efficiency of your fridge translates into less amperage draw, which at best will probably be around 25amps per day and might be double that in hot weather. Also, keep in mind that whatever power you draw out of the battery you will have to put about 1.5 times back in i.e. allowing for inefficiencies in batteries, charger units (including solar panels), cabling, etc. A big drain on your battery power might be the cable from your second battery (in the engine bay) to your fridge near the rear of the vehicle. That loss of power is commonly called "voltage drop" and can be as much as 2 VDC i.e. with a fully charged battery (say 12.6VDC, the fridge might be cutting in and out because voltage at the fridge end of the cable is somewhere between 10.5VDC and 11VDC. For this reason, many ute owners locate their second battery in the tray and sit the fridge and/or freezer right alongside it.
Just as a guide, a start battery is considered to be "flat" when the amount of charge it holds falls below 12VDC. The 10.5VDC trip on a fridge is there to avoid (but not prevent) fatal discharge of a battery. If you regularly run your battery down to 10.5VDC it is more likely to suffer premature death. Deep cycle batteries will put up with significantly more of such use, but because more power is taken out they take longer to recharge i.e. about 2 to 3 times longer. Unfortunately, fast charging any battery reduces the life of the battery.
As to how many batteries will suit your needs, depends upon the all of the above. If you are only using your fridge for weekends, then one deep cycle battery (in addtion to your start battery) will probably be enough. If you are going away for extended periods then 2 deep cycle batteries may be necessary, especially if the kids are opening the door of the fridge every five minutes, and you will need some means of recharging those batteries.
Only you can tell how long the piece of string is.