Outer Limits 4x4 Board

Apart from power issues, what is so special about car fridge/freezers that makes them cost so much?

You can get a 70L bar fridge for $100...anyone modded one for the car?

(1) Car fridges run on 12V
(2) They are made to handle bouncing around in the back of a car
(3) They are made to use minimal power

If you got a bar fridge and an inverter it would work, but suck heaps of power and the inverter would make the cost about the same as just buying a real car fridge.

If you mainly go camping (i.e. stay at the same place for a long time), then a cheaper option is a 3-way fridge (12V/240V/Gas). Can run them on 240V at home, 12V in the car (but not with engine off as they such heaps of power), and gas when camping.

When you transport a normal fridge, you are meant to let it sit before using... Might be due to the refrigerants used.

Waeco's normally use thermocouple technology which is lightweight and cools to about 30 degrees below outside temperature. This is a cooler and not a refrigerator.
The fridges use Kompressor technology, which is more expensive, but gives you freezing temperatures.
These also draw minimal power when in use.

The higher costs would be mainly due to mass production of the bar fridges for your home, whereas the Waeco type fridges are more comapct, use newer technologies and are targeted at a specific buyer - hence they can justify a higher price.

Thanks for your input!

I understand build quality is an issue, that can be overcome.

Low power seems to be the key.

About that myth of not moving fridges and leaving them for a few hours before you turn them back on...how do car fridges differ in that department?

check this out............ should answer that question

http://www.fridge-and-solar.net/fridgetest1.htm

Interesting study - he didn't mention the cost of the inverter though - looking at Jaycar prices works out about $300 minimum.

As for what makes car fridges moveable - as I understand it the danfoss compressor (all the good ones use this brand) is mounted in some sort of swing or cradle, so it is able to work the same at all angles and handle vibration, etc. Anyone have more info?

foodie wrote:About that myth of not moving fridges and leaving them for a few hours before you turn them back on...how do car fridges differ in that department?

I'm happy to believe it - I don't think it's a myth.

I worked as a removalist for a while. The company had a contract with the (then) Department of Administrative Services, who organised moves for government employees. They found they were getting heaps of insurance claims for fridges failing shortly after moving. They introduced a policy that the fridge shouldn't be turned on for 2 hours after delivery, and found they weren't getting anywhere near as many claims.

Their theory is that the refrigerant gets shaken up in transit, and becomes aerated. If the motor is turned on the compressor seals aren't lubricated properly, so they wear and quickly fail. Allow the refrigerant to settle, and the seals are happy.

I guess a car fridge has a more expensive compressor, probably with better seals, which isn't affected by this problem. Mobile fridges are also designed to run on significant angles, where domestic fridges are normally installed on a level floor.

Cheers,

Scott

About that myth of not moving fridges and leaving them for a few hours before you turn them back on...how do car fridges differ in that department?

its not really a myth, i repair domestic fridges for a living, i also buy sell and deliver 2nd hand fridges. if they are kept upright during transportation you can turn them on straight away. if they are laid on their sides, they need to be stood upright for a few hours before turning them on. the reason being that when they are laid down on the side, the oil from the compressor/motor runs into the condensor, if you start it straight away it will be running dry and can damage motor/compressor. it can also create blockages in the fine capillary tube. allowing the fridge to stand for a few hours allows the oil to run back to where it belongs.
Now back on topic. a bar fridge will run through an invertor, but it will need to be a big invertor, around 1000 watts which is not a cheap item, how long the fridge would last i dont know. but domestic fridges arent really designed to run on the move. car fridges have better designed compressors with the internals tightly secured. household fridges dont. just turn your bar fridge off and tap the compressor with your hand, you can actually hear the internals move [/quote]

I heard the fridge myth was because liquid refridgant gets into the compressor instead of gas refridgant causing the compressor to hydrolic and stuff up.
Also the Weaco's use compressors.
My weaco kept things frozen, and refroze things when the battery went flat in the simpson no worries. And the temp difference was way more than 30degrees C.

nice to hear from the pro's!

my dream of a tightass fridge mod is being shattered by realism and facts! DOH!


Whats you opinions on 3way fridges. And buying 2nd hand?

Chucky wrote: Also the Weaco's use compressors.
My weaco kept things frozen, and refroze things when the battery went flat in the simpson no worries. And the temp difference was way more than 30degrees C.

SOME Waeco's use compressors. The others use thermocouples, which i stated are the 'coolers' and not refrigerators. All Waeco car fridges use Kompressor technology. And i have never said they did not.


If you cared to read my post:

HotFourOk wrote:Waeco's normally use thermocouple technology which is lightweight and cools to about 30 degrees below outside temperature. This is a cooler and not a refrigerator.
The fridges use Kompressor technology, which is more expensive, but gives you freezing temperatures.

HotFourOk wrote:

Chucky wrote: Also the Weaco's use compressors.
My weaco kept things frozen, and refroze things when the battery went flat in the simpson no worries. And the temp difference was way more than 30degrees C.

SOME Waeco's use compressors. The others use thermocouples, which i stated are the 'coolers' and not refrigerators. All Waeco car fridges use Kompressor technology. And i have never said they did not.


If you cared to read my post:

HotFourOk wrote:Waeco's normally use thermocouple technology which is lightweight and cools to about 30 degrees below outside temperature. This is a cooler and not a refrigerator.
The fridges use Kompressor technology, which is more expensive, but gives you freezing temperatures.

Hot4 - you are talking about Peltier Elements, not thermocouples. Peltier elements are also called thermoelectric elements. A thermocouple is a device made for measuring temperature, not heating/cooling. Most waecos that I have seen are real compressor fridges, not simply peltier coolers.

Ohh yep, sorry Ben, I accidently used the word thermocouple after reading the pyrometer post... lol
I was meant to say thermoelectrics.. got a bit confuzzled... lol

The can cooler type Waecos (and now a lot of cheap copies) use peltier elements to cool the items inside. These cannot get to the low temps like the refrigerator/freezer models.
These are cheap to manufacture - its all solid state materials used.
I have a 30 dollar jobby from DSE and it works wonders for keeping drinks cold.

But as I said previously, the fridges use Kompressor technology.
This is a much more complex system, which is why its dearer to produce and buy, but cools much more effectively. More like a normal fridge.

http://www.waeco.com.au/products.asp?catId=6

foodie wrote: Whats you opinions on 3way fridges. And buying 2nd hand?

if you're staying in 1 spot for long periods a 3 way rocks. 12v in the car (like said don't leave them on 12v with the car off too long the are power hungry), 240v at home and gas at camp. They will easily go a week on a 9kg gas bottle you need to be 100% sure they're level in use though......... not being level won't hurt em but they won't really cool properly.

I bought a 45l waeco fridge/freezer off this board for 400 and its been tops Freezes great, I keep blowing up cans trying to get the beer just that little bit colder Like all things 2nd hand though if it stops then too bad........ but these products are pretty reliable regardless of brand and should give a long life