LEC 32 litre freezer should I worry?

[ericmark]

My mothers fridge/freezer does not have enough freezer capacity to allow a weekly shop so we bought a second freezer which sits on top of the main one and the carers move food down as the food in bottom one is used.

This small A+ 32 litre freezer by LEC will hold around 30 ready meals each time it is emptied it's turned off so gets a regular de-frost. It's about 2 years old.

I had no reason to suspect there was anything wrong with it but as an experiment I decided to plug it into an energy meter to see how much it used. I thought I had made a mistake so re-tested. Test time 335 hours 39 minutes and power used 9.66 kW and run watts 28. This equates to 252 kWh/annum but the unit is rated at 146 kWh/annum. The extra power used is not really a worry but the mark/space ratio run to idle is because I have worked out it's running for 100% of the time.

Since finding this out I have noted it's never idle however never noted any food which is not fully frozen. Neither have I noted ice cream being too hard. The freezer is shown here

Although a motor could fail at any time to have insulation fail after just 2 years seems a bit odd. All my temperature senders only go down to zero so inside temperature is guess work.

Even at £50 a year it does not make economic sense to change it only one we could get is the same make and model and they cost £100 so would save £25 a year if changed which means 4 years to break even but last one only lasted 2 years so no point.

I am just wondering if I have missed something silly.

 

[bernardgreen]

What you have found does seem a bit odd.

I have the same one. With the switch set to normal it seldom runs for more than a few minutes at a time unless the door has been left open for a long time.

The rated consumption of most appliances is when the appliance is run under ideal conditions. I recall vaguely for freezers these ideal conditions are with the freezer full and only opened once or twice a day. So it is possible that under normal use the actual consumption per year could be double the calculated average.

It is the loss of cold air when the door is opened that adds to the running costs as the replacement warm air as to be cooled. Hence a full freezer will be cheaper to run as there is less air changes.

 

[plugwash]

Some freezers have (or at least used to have) a "fast freeze" button/switch, I wonder if that could have either been left on or got stuck on even though it appears to be off.

A partial failure in the motor/compresor arrangement causing the freezer to never reach it's target temperature also seems like a possibility.

 

[JohnW2]

Test time 335 hours 39 minutes and power used 9.66 kW and run watts 28. This equates to 252 kWh/annum but the unit is rated at 146 kWh/annum. The extra power used is not really a worry but the mark/space ratio run to idle is because I have worked out it's running for 100% of the time.

[I presume you mean 9.66 kWh]. As bernard has suggested, I would not be all that surprised to find that the achieved power consumption was about 73% higher than the manufacturer's quoted (probably 'ideal circumstances') figure. However, to have a 100% duty cycle is clearly not right. Mind you, if the 'running current' really is always around 28W, then even the manufacturer's figure (146 kWh/annum) implies an onff ratio of about 1.47:1, which sounds surprisingly high.

Kind Regards, John

 

[conny]

You can buy thermometers to put in your fridge/freezer that go down to -30c
Ideally freezer temperatures should be about -18c and fridges +3 or 4c

 

[AdrianUK]

...........Test time 335 hours 39 minutes and power used 9.66 kW and run watts 28. This equates to 252 kWh/annum but the unit is rated at 146 kWh/annum. The extra power used is not really a worry but the mark/space ratio run to idle is because I have worked out it's running for 100% of the time.........

My first question would be ...... 28 Watts running...... Nah!

If this is what your meter is suggesting ..... then it time to chuck it in the bin!

Most of these energy meters are wildly inaccurate at low powers & with devices which have a low power factor (most assume a pf of 1.0 & a voltage of 230V ... hence assuming that all the current equates to Watts ..... but that isnt true to a motor.... there is a reactive component to the current which the power meter cannot separate out because it cant measure the angle between the voltage & the current.)

Adrian

 

[ericmark]

I hunted yesterday while out for a thermometer to measure -18 and failed. I tried adjusting temperature that also failed to stop freezer so think it must be thermostat. Today found Maplin sell thermometers for freezer so likely that's the quick way to get one.

Energy meter results with other items have been as expected so would expect the results to be reasonable in accuracy.

Yes kWh missed out the hour sorry. At £16 for new thermostat may just order one and change it anyway.