engel not freezing

[rockcrawler31]

hey all.

i have an older engel 30 litre, it seems to chew a fair bit of juice and will flatten an N70 deepcycle in a day, but can't seem to freeze stuff.

went out on the weekend and i kept the meat, beer and milk in it and salad in a little cooler box. I had it on the coldest setting all weekend, with low ambient daytime temperatures, cool night temps and good battery power. It was barely able to get the milk to slushy ice consistency.

any ideas what the problem may be. i only have .2 volts drop from the battery to the rear of the car.

if i have to sell it, can anyone tell me what is a good model in either the waeco or engel range in about 40 litres, second hand, and what kind of power consumption between the two

i have considered an evakool or refridgeration research fridge, and they seem to come up trumps with power use due to good insulation but they take up a load of room.

also, i was going to sew up a canvas cover to help with the insulation. i was going to put a layer of neoprene then a layer of shiny side out aluminium foil then the canvas. Do you think this would help with insulation or not worth the effort.

cheers all

[-Scott-]

Are you sure it's not a dud battery? You really need to monitor the battery voltage while it's running - 0.2V drop sounds reasonable, but is the final figure 11V or 12V?

If it really is the fridge, I'd suspect condenser fan or refrigerant problem. Are all fans working properly?

An insulated bag won't hurt, but the shiny stuff is intended to reflect radiant heat such as sun light. To do this, it has to be exposed. If it's not the outside layer, it won't make much difference.

Cheers,

Scott

[rockcrawler31]

cheers mate

getting about 13.4 to 13.5 volt as an average at the socket or thereabouts.

the fridge is an old one, and doesn't seem to have a fan. maybe if i get one of those 12v computer fans and hook it up on the fridges power supply to help cool the rad would that help??

how costly or successful is re gassing these things?

[-Mick-]

might sound silly but was the fridge actually running properly As in could you hear the compressor doing its business and did it sound ok

Sounds like your voltage was ok but if it wasn't venting properly the motor could have been doing the thermal cut off thing???

Try it in a controlled condition like on the floor in your house off the mains and see if it works ok in the cool

[currentlyoffline]

An insulated bag won't hurt, but the shiny stuff is intended to reflect radiant heat such as sun light. To do this, it has to be exposed. If it's not the outside layer, it won't make much difference.
Scott

Have a look at a genuine Engel Fridge bag then. They are usually grey or brown on the outside.....
Reckon you can't go past a Trailblazer myself, especially since you are from Brisbane. Trailblazers have 75mm thick walls.

[-Scott-]

An insulated bag won't hurt, but the shiny stuff is intended to reflect radiant heat such as sun light. To do this, it has to be exposed. If it's not the outside layer, it won't make much difference.
Scott

Have a look at a genuine Engel Fridge bag then. They are usually grey or brown on the outside.....

And where do they have shiny stuff?

[j-top paj]

the shiny stuff is on the inside.

[-Scott-]

the shiny stuff is on the inside.

OK. That's got me stuffed!

[HotFourOk]

the shiny stuff is on the inside.

OK. That's got me stuffed!

The same as you use flashing under a tin roof... it has a shiny side much like foil.. the sheets of tin block the direct sun, but the flashing helps to insulate the inside, even though the shiny surface does not reflect the suns rays directly... It just lowers the amount of heat radiating into the house.

[-Scott-]

Inside the ceiling I understand - tin gets hot, shiny flashing stops hot tin radiating into ceiling space.

If it's reflecting radiant heat, why would you put it inside a fridge bag? Don't you want the heat to escape?

Dark colour canvas will absorb any radiant heat e.g. sunlight. Why wouldn't you put the shiny stuff outside, to reflect incident radiation?

On the other hand, dark colours radiate heat better - so if your fridge is shaded, the dark colour will help shed heat. But the shiny layer is reflecting any radiant heat coming from the fridge, which strikes me as self-defeating.

Obviously, I'm missing something here. Help?

Scott

[rockcrawler31]

hey scott

as i see it and the way i was going to design it, light colored canvas as per your point about dark colours absorbing heat,

the silver foil wont stop heat getting out, that is the job of the compressor system and radiator assembly on the fridge, but it is designed to stop the heat from the ambient temps outside getting in. In a similar way that you are supposed to wrap the spuds in your fire with the shiny side of the foil in to trap the heat in.

The neoprene also helps in this as it creates an air gap i believe. Air is actually fairly crap at conducting heat which is why a full fridge stays colder with less power than an empty one. I believe this is how styrofoam insulates as it too creates an air gap. someone please correct me if i am wrong.

[Gruntahunta]

Sometimes fridges (in vehicles) get shook up a bit much and the refrigerant gets bubbles in it and doesn't work efficiently. If you slowly roll your fridge forwards or backwards in a 360 degree turn it will settle the refrigerant and the fridge efficiency will pick up again. I have to do this to my chescold occasianally. Maybe doesn't work with all fridges but certainly does with mine. I also have 2 computer fans in the rear and one inside to circulate air and it works just great. I barely have to have it turned up to be really cold.

Hope this helps................Pete!