Fridge for £79.99

[CAPTAIN FANTASTIC]

I bought a new tabletop fridge from Argos for £79.99. We have been using it on the boat, for the last two days, it has 5 settings on the thermostat, when I set it on 2 and above, the freezer compartment gets icy, on setting 1 there is no ice, it just keeps everything very cold. The power consumption is ~135kAh per year, however, in practice it is much less when left on setting 1 or 2; I use an inverter. I thought the fridge would run the batteries down but it did not; good value for money.

 

[Hadenough]

So how are you keeping the batteries charged?

 

[CAPTAIN FANTASTIC]

Rutland 913; but the fridge does not appear to use much on the lower setting.

 

[Hadenough]

So let's be clear. You are powering a 240v fridge via an inverter and charging the batteries with a Rutland 913? What is your bank and for what durations are you running the fridge?

 

[nigelmercier]

... The power consumption is ~135kAh per year...

That's 370Ah per day, or 15A!

 

[stevebrassett]

That's 370Ah per day, or 15A!

It's actually 139KwH per year, which works out at just over 2.6A at 12 volts, average.

The price has gone down by 10 quid, as well.

 

[Rum Run]

Assuming it is this product:
http://www.argos.co.uk/static/Product/partNumber/4810423.htm
It states 139KWh/year, so 0.3808 KWh /day. At 12.5V, about 31Ah/day plus whatever the losses of the inverter are, say 20% so maybe 37Ah/day. It's an intermittent inductive load with a high starting current so the efficiency of the inverter is a bit of a guess.
Taking the 37Ah/day, then that's 1.55 Amps constant input, so if the wind is steady for 24 hours (!) the 913 allegedly needs to see about 10Kn wind if I RTFM correctly. This obviously disregards charging losses, marketing lies and someone leaving the fridge door open.
The figure of 139KWh/year will come from a standardised test using dummy contents and a set door opening and contents placement scheme, which bares little resemblance to actual usage but does provide a comparison across fridges. The tests are done in an environmental testing chamber so the ambient temperature etc is controlled. Some of the results I used to see for commercial retail chillers made me wonder about the methodology TBH.
So, I'd say that with a decent battery bank, a decent inverter, decent wind across the deck and assuming the usage is no more than the A+ rating allows, then cold beer should ensue. I'd be wanting a low-volt sensing off switch on the thing though!

 

[William_H]

The concept of running a small domestic fridge on an inverter is not so stupid. Considering the intial cost and the fact that many will run on shore power anyway for much of the time. I understand that the inductive load nature of the fridge compressor motor would require a true sine wave inverter. This may well be what the OP is using however I would urge him to test actual 12v supply current when the fridge is running to confirm all efficiencies are as they should be. good luck olewill

 

[CAPTAIN FANTASTIC]

The concept of running a small domestic fridge on an inverter is not so stupid. Considering the intial cost and the fact that many will run on shore power anyway for much of the time. I understand that the inductive load nature of the fridge compressor motor would require a true sine wave inverter. This may well be what the OP is using however I would urge him to test actual 12v supply current when the fridge is running to confirm all efficiencies are as they should be. good luck olewill

No, I am using a low cost (non true sine wave ~£70) 1000 watt inverter which runs my new lcd TV and now the fridge. The compressor on the fridge is small, but big enough to keep things cold and even icy.

 

[CAPTAIN FANTASTIC]

So let's be clear. You are powering a 240v fridge via an inverter and charging the batteries with a Rutland 913? What is your bank and for what durations are you running the fridge?

Yes, it is a 240v fridge running via a low cost 1000 watt inverterI keep the fridge pluged in all the time; I use 4 x 110 amps batteries which are a few years old now. I also have an engine start battery.

 

[CAPTAIN FANTASTIC]

Assuming it is this product:
http://www.argos.co.uk/static/Product/partNumber/4810423.htm
It states 139KWh/year, so 0.3808 KWh /day. At 12.5V, about 31Ah/day plus whatever the losses of the inverter are, say 20% so maybe 37Ah/day. It's an intermittent inductive load with a high starting current so the efficiency of the inverter is a bit of a guess.
Taking the 37Ah/day, then that's 1.55 Amps constant input, so if the wind is steady for 24 hours (!) the 913 allegedly needs to see about 10Kn wind if I RTFM correctly. This obviously disregards charging losses, marketing lies and someone leaving the fridge door open.
The figure of 139KWh/year will come from a standardised test using dummy contents and a set door opening and contents placement scheme, which bares little resemblance to actual usage but does provide a comparison across fridges. The tests are done in an environmental testing chamber so the ambient temperature etc is controlled. Some of the results I used to see for commercial retail chillers made me wonder about the methodology TBH.
So, I'd say that with a decent battery bank, a decent inverter, decent wind across the deck and assuming the usage is no more than the A+ rating allows, then cold beer should ensue. I'd be wanting a low-volt sensing off switch on the thing though!

Yes, this is the one, it looks like its gone down by £10 since Friday morning!!

 

[nigelmercier]

No, I am using a low cost (non true sine wave ~£70) 1000 watt inverter which runs my new lcd TV ...

Ouch!

 

[AngusMcDoon]

It's actually 139KwH per year, which works out at just over 2.6A at 12 volts, average.

The price has gone down by 10 quid, as well.

My Waeco CF18 compressor coolbox uses on average in a UK summer 420mA at 12V keeping it at 4C, but it is a lot more expensive to buy.

 

[Dougal]

My Waeco CF18 compressor coolbox uses on average in a UK summer 420mA at 12V keeping it at 4C, but it is a lot more expensive to buy.

Oh poo! Just paid out £80 for a Halfords 12/240v cool box that rubbish

 

[Concerto]

I bought a new tabletop fridge from Argos for £79.99.

I have one of these at work and not that impressed. Yes it works and can certainly keep things cold/frozen. The big problem is the amount of condensation that comes from the small freezer/chiller unit. There is nothing to collect it and the bottom of the fridge is continually getting wet and then draining out when the door is open.

 

[CAPTAIN FANTASTIC]

I have one of these at work and not that impressed. Yes it works and can certainly keep things cold/frozen. The big problem is the amount of condensation that comes from the small freezer/chiller unit. There is nothing to collect it and the bottom of the fridge is continually getting wet and then draining out when the door is open.

I think I can live with it

 

[CreakyDecks]

Curious that it says its ambient temperature operating range is 16 - 32 deg. I can understand there being a maximum but can't understand why the minimum is so high.

 

[CAPTAIN FANTASTIC]

Curious that it says its ambient temperature operating range is 16 - 32 deg. I can understand there being a maximum but can't understand why the minimum is so high.

I dont know. I am in the yacht at the moment and the fridge works fine keeping everything nice and cold on the lowest setting; I am suprised how quiet it is too. So as someone else discovered that the price is now £69.99, it represents great value for money; even if it is used as a cool box only.