coolboxes

[Denise4]

Hi, We want to get a decent coolbox as caravan fridge not big enough. They vary a lot in price. Could someone explain what the difference is between the cheapies and the £100+ boxes. Also any recommendations would be appreciated. Thanks Denise.

 

[RodneyN.Wales]

I bought one from Halfords when on offer at around

 

[ProfJohnL]

Hello Denise

There are basically two type of cool boxes, A) the ones that use the peltier effect, and B) the absorption principal.

The peltier effect devices are generally sole as 'electric Cool Boxes' and are fine as long as you understand that they will only chill to about 15 to 20 degrees below the ambient temperature. They will not produce (Ice cubes). The boxes sometimes have the additional benefit of being able to keep the contents warm. This is either achieved by a switch, or simply turning the 12 volt dc plug over. The come in all sorts of different sizes. They also tend to be noisy as they use a small 12V fan to extract the waste heat.

The absorption principal is capable of doing much more. Your existing caravan fridge uses this principle, and is capable of cooling to produce ice The other advantage is is that they can use multiple fuel sources (just like your caravan) 12Vdc, Mains 230 V Ac and LPG. For versatility and effectiveness the absorption is better, but it is heavier and more expensive but also quieter.

Both systems can use 12V dc, and both will consume around 8 Amps, so in practice the 12V dc systems are only really any good when the engine is running, However, Many of the peltier systems come provided with a 230V ac to 12Vdc power supply, and these make practical sense if you have a mains hook up available. (outside in the awning to keep the tubes of larger cool)

I run a Scout Group and for longer stays I use an absorption box, but for picnics I use a Peltier system.

I have never come across a cool box that monitors the supply voltage to prevents flattening the car battery (Sorry Rodney I am open to being corrected about this).

 

[Denise4]

Hello Denise

There are basically two type of cool boxes, A) the ones that use the peltier effect, and B) the absorption principal.

The peltier effect devices are generally sole as 'electric Cool Boxes' and are fine as long as you understand that they will only chill to about 15 to 20 degrees below the ambient temperature. They will not produce (Ice cubes). The boxes sometimes have the additional benefit of being able to keep the contents warm. This is either achieved by a switch, or simply turning the 12 volt dc plug over. The come in all sorts of different sizes. They also tend to be noisy as they use a small 12V fan to extract the waste heat.

The absorption principal is capable of doing much more. Your existing caravan fridge uses this principle, and is capable of cooling to produce ice The other advantage is is that they can use multiple fuel sources (just like your caravan) 12Vdc, Mains 230 V Ac and LPG. For versatility and effectiveness the absorption is better, but it is heavier and more expensive but also quieter.

Both systems can use 12V dc, and both will consume around 8 Amps, so in practice the 12V dc systems are only really any good when the engine is running, However, Many of the peltier systems come provided with a 230V ac to 12Vdc power supply, and these make practical sense if you have a mains hook up available. (outside in the awning to keep the tubes of larger cool)

I run a Scout Group and for longer stays I use an absorption box, but for picnics I use a Peltier system.

I have never come across a cool box that monitors the supply voltage to prevents flattening the car battery (Sorry Rodney I am open to being corrected about this).

Thanks guys. Will be investing in one of the absorption boxes as thinking of going abroad next year so the cheaper ones probably won't chill in hotter climes. Denise

 

[RodneyN.Wales]

Hello Denise

There are basically two type of cool boxes, A) the ones that use the peltier effect, and B) the absorption principal.

The peltier effect devices are generally sole as 'electric Cool Boxes' and are fine as long as you understand that they will only chill to about 15 to 20 degrees below the ambient temperature. They will not produce (Ice cubes). The boxes sometimes have the additional benefit of being able to keep the contents warm. This is either achieved by a switch, or simply turning the 12 volt dc plug over. The come in all sorts of different sizes. They also tend to be noisy as they use a small 12V fan to extract the waste heat.

The absorption principal is capable of doing much more. Your existing caravan fridge uses this principle, and is capable of cooling to produce ice The other advantage is is that they can use multiple fuel sources (just like your caravan) 12Vdc, Mains 230 V Ac and LPG. For versatility and effectiveness the absorption is better, but it is heavier and more expensive but also quieter.

Both systems can use 12V dc, and both will consume around 8 Amps, so in practice the 12V dc systems are only really any good when the engine is running, However, Many of the peltier systems come provided with a 230V ac to 12Vdc power supply, and these make practical sense if you have a mains hook up available. (outside in the awning to keep the tubes of larger cool)

I run a Scout Group and for longer stays I use an absorption box, but for picnics I use a Peltier system.

I have never come across a cool box that monitors the supply voltage to prevents flattening the car battery (Sorry Rodney I am open to being corrected about this).

Hi John - The "Switch" I mentioned is a bit of electronics that detects if a charge is going into the car battery. If it is then it switches on the "Coolbox". I can overide it but have found, to my cost, it will drain a new car battery withing 4/5 hours. No issue when running off the Caravan battery as am usually pluged into the mains so its constantly charging.

 

[ProfJohnL]

Hi John - The "Switch" I mentioned is a bit of electronics that detects if a charge is going into the car battery. If it is then it switches on the "Coolbox". I can overide it but have found, to my cost, it will drain a new car battery withing 4/5 hours. No issue when running off the Caravan battery as am usually pluged into the mains so its constantly charging.

Is this circuit fitted to the cool-box? Please give the manufacteures name and model if you can, or is the charge/Fridge relay that should be fitted to a car as part of the towing equipment? in which case my statement stands.

 

[RayS]

Very comprehensive reply from John L but another factor is that the thermoelectic boxes generally do not have a thermostat to prevent overcooling. They will cool down - say - 20 degrees below ambient air temperature. If you have them outside the caravan and forget to switch them off overnight, it is quite possible to freeze the contents which is bad news if it happens to be salad veg, and not too good if it hapens to be fizzy drinks.

The absorbsion type usually have thermostats but perhaps only when running on 230v. mains, not gas or 12 volt dc.

 

[ProfJohnL]

Hello Ray

whlst I agree that the peltier effect units tend not to have thermostats, I have not encountered one that does freeze in UK weather conditions.