Fridge Temps

VK3FEMT · Senior Member

Fridge Temps

coongoola · Member

Stew,

We have the Jaycar weather station with two remote sensors ( $69 for the unit ) and we ended up turning down the temperature. We have a sensor in the frig and the freezer. Freezer happy on -15 and frig around 2 degrees.

Hooroo

Pat

VK3FEMT · Senior Member

Ok thanks, I've got mine on -15 at the moment, mine is a one setting for both type machine.

I was going to get a fridge/freezer at Rays Outdoors but I had some problems, most on here suggested Engel, I did some measurements and from memory the Engel 80L would not fit through the bus door, and it would takeup most of the passage space. Both the Engel and Waeco were beyond my spending limit.

I brought this one from Ebay new, its a no-name type arrangement cost $650 for a 70L and without a word of a lie, there is more space in this then there is in the Waeco 110L model that I was originally looking at. I don't know how Waeco come up with their capacity sizes but the freezer in this is bigger then the Waeco and the fridge part is also a deeper meaning I can get 2L milk etc into it, which I couldn't in the Waeco.

So far I am happy with it and it is doing for what it is designed, coldness...

I was just wanting to know re running temps as I am heading bush this weekend for a road-test, or bush-test as it is, and didn't want it running all the time on the battery or I would be in trouble.

I am going to get a 700cca battery fitted today and in another few weeks I will get a second one as well, then put the second battery on a solenoid isolator and run the fridge and whatnot off it.

twobob · Guru

This may help, on deciding fridge/freezer temps.

FOOD SAFETY Aust, requires all commercial outlets to monitor their temps daily. The requirement is that

all Frozen, be hard, ie <0 degree
All fridge, be <5 degree

There are conditions also, about the time food can stand outside of these temps, before it is eaten or disposed of, by memory, its 4 hours total.

Fridge/Freezers, have a swing of about 2 degree, between cutting in and cutting out, so runs at 5 degree, and turns off at 3 degree. (-13 to -15 freezer)

If you have one setting for both, set it to have the fridge right, and the freezer will take care of itself.

A setting of -10 or -15 degree, for freezer, should get it down to temp, relatively quickly, and allow for extended off time, IMO.

-- Edited by twobob on Friday 22nd of May 2009 08:59:11 AM

Wombat 280 · Guru

When you fit your second battery be sure it's the same capacity and the alternator of the tug will be capable of producing the necessary charge rate . Some alternators are flat out running the vehicle electronics let alone any high demand accessories

I find that running fridges on battery power they chew up the power like a bloody open bar heater so don't expect it to run for very long and watch out you don't fully drain your cranking battery otherwise in the bush you will stay.

Frozen is frozen why the minus 15 degrees it all sounds like a lot of power consumption to make sure it stays frozen . . If you don't have kids opening and closing the lid every 15 seconds it should remain frozen for a couple of days, if the wall insulation is any good. Some fridges / freezer thermostats are extremely temperature sensitive and a slight drop of internal temps causes the unit to kick in well before the tucker has sensed any change .

When I go bush you would be surprised how little refrigeration I need as most times are UHT or tinned + fresh vegs . No Milk, if needed UHT vegs don't need it and 1/2 doz beers left in the river this time of year and that's the sum total

Enjoy your shake down cruise

Lets know how it goes

-- Edited by Wombat 280 on Friday 22nd of May 2009 05:34:34 PM

kenmarg · Senior Member

hi. just a bit of a guide,ice-cream in the freezer starts to melt at -14. so if you freezer come down in temperature,and then have to turn it up to say -20. thats when you get a disease called botulism. which makes you very crook. in the fridge side,milk runs at +4,tomatoes at +10,so you have to average it out. i know it is annoying,that it switches on and off all the time ( check the door seal to see if it is leaking cold air ) but i have found with our fridge truck,the colder you can run the freezer, the better you can hold the food on a hot day. when you put a item of food in a freezer,it stays at the temperature that it was when you put it in. only a blast freezer will drop the temperature on your product.

twobob · Guru

Kenmarg
I know this is not the time to take on someone, but what you have said seems incorrect.

Botulism is not directly associated with icecream, although, any food can have it. If stored correctly, it is safe. Icecream will soften the closer it gets to zero, and most people like their icecream hard.

I believe you are talking in trucking terms, where there is a high exchange of air volume, and therefore a high demand on the refridgeration. Therefore, yes, the colder the better.

There is no averaging of temp, for multiple products in the one compartment. The lesser value is the one to use. So Milk and Tomatoes together is 4 degree.

When I put water into my freezer, it comes out as ice, so it has not stayed at the same temp as when placed in.

For our needs, I believe we should use Food Safety Aust, as a guide

-- Edited by twobob on Friday 22nd of May 2009 10:43:49 PM

kenmarg · Senior Member

what do you mean. TWOBOB. "by take someone on". you want to "read" my post. i didnt say you could get botulism from ice-cream. you get botulism from letting foodstuff thaw out and then re-freezing it. if you are trying to question my knowledge on refrigeration, ( 43 years of managing a major freezer,and owning my own fridge trucks ) i dont have to refer to another internet site.

VK3FEMT · Senior Member

Well I don't even know what Botulism is, neverheardofit until now :)

As for the temps, it would appear there is something looney going on with the gauge on the unit itself. If I have it running at say -19 its lowest temp, and its been that way for an hour or so, if I disconnect the power and plug it back in a minute later the digital mahjigger will say -9 or something equally as silly. I know it hasn't dropped that far in the space of a minute.

This problem only seems to be occuring on 12v side of things.

Anyway it seems to be working finely, I tried it at -10, -13, -15 and they didn't seem to freeze stuff enough (running on 12v only). So it looks like -19 is the whack.