Compressor fridge cycling times

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Ambient 22c and 5 available settings on fridge

Setting 4 (-2.5c)

On 3m 30s
Off 2m 45s
On 3m 30s
Off 2m 48s

Temp increase during OFF of 0.1c

Setting 2 (3.3c)

On 2m 39s
Off 2m 49s
On 2m 35s
Off 2m 57s

Temp increase during OFF 0.3c

I have checked the seal all round there is resistance when opening the door. During experiment seal was slightly broken due thermometer cable.

Any thoughts very welcome as running 50% of the time is going to batter my battery
Break out tight ass and buy a small AA++ £70 and a smart inverter.
 
The fridge is 25 years old, maybe this is the problem. Obviously I have no way of knowing if it has ever been topped up.

As it is sunny today I am doing an experiment with the thermostat
Have you got a make and model?
 
Have you got a make and model?
Engel. Sorry but photo is best I can do with regards to model

20210917_142947.jpg
 
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Just chill it's now winter. What about a good shake or is that the other type.
I did like that video about added fans and insulation.
I'm testing mine as it the only item on in the van. So when battery is full for a few days I'll post sc 30 day harvest.
 
Interestingly it seems you can date Engel fridges by the current the compressor draws...

Decade of Manufacture / Current draw when ON
70's / 6 A
80's / 4.5 A
90's / 3.7 A
2000-on / 2.5 A

IF the unit is achieving the temps you would expect and not struggling to keep cold...
It's possible you have got a thermostat with a particularly tight 'dead band'...

Our comfort cooling aircon systems are usually calibrated to run plus/minus 2 degrees (so controller set to 20 degrees room can get up to 22 degrees before the unit starts cooling and cool down 18 degrees before shutting off.... To prevent the compressor stop/starting continuously.
(not quite so cut and dried now we have inverter (variable speed) compressors)
Server room units/process cooling (close control) are typically +/- 1 degree.
 
Interestingly it seems you can date Engel fridges by the current the compressor draws...

Decade of Manufacture / Current draw when ON
70's / 6 A
80's / 4.5 A
90's / 3.7 A
2000-on / 2.5 A

IF the unit is achieving the temps you would expect and not struggling to keep cold...
It's possible you have got a thermostat with a particularly tight 'dead band'...

Our comfort cooling aircon systems are usually calibrated to run plus/minus 2 degrees (so controller set to 20 degrees room can get up to 22 degrees before the unit starts cooling and cool down 18 degrees before shutting off.... To prevent the compressor stop/starting continuously.
(not quite so cut and dried now we have inverter (variable speed) compressors)
Server room units/process cooling (close control) are typically +/- 1 degree.
Thank you for your interest and help
 
Anyone have any idea what the little red button that looks like a reset button might do?

My Japanese is a bit rusty :sneaky:

20210918_150556.jpg
 
Time to get your google translate app on your phone on to it!
Most likely a reset button though (Its exactly like the one on my house immersion heater overheat reset)
Press it with a pen and see if it works, but would be the first thing to check if your fridge stops.
Cheers from Stratford.
Dave.
 
My fridge has a removable freezer compartment. Is the compressor working harder or is it just the thermostat that control's on and off ?.

What is the running temp of a compressor ? in winter could it be on high setting 5/5 and 70ltrs become a freezer ?.
 
My fridge has a removable freezer compartment. Is the compressor working harder or is it just the thermostat that control's on and off ?.

What is the running temp of a compressor ? in winter could it be on high setting 5/5 and 70ltrs become a freezer ?.
First question; Little unsure what you are asking tbh, are you asking if the compressor is cutting out due to inbuilt protection?

Second question; I don't know, how would I determine this, contact thermometer?

Third question; As setting 4 was maintaining -2.5c then I suggest 5 would indeed would be very low, not like a domestic freezer though
 
-2.5 is good , that will do if I need it over Christmas. For when the lights go off. I'll get more insulation and some fans too. To help
Thanks
 
If its any help. Some theoretical figures from my Dometic fridge:
Spec'd current load is 5.9A which if run for 24 hours would consume141.6 Ah
Manufacture nominal power usage is approx 40Ah per 24 hours
So duty cycle would be 40 / 141.6 = 28%

Roughly speaking, in theory, on for 20 mins in every hour.
 
Those fridges you have shown here seem to use a lot, mine is 250w on 230v through a smart soft start inverter, not sure how much it uses though as its rated at 600w.
 
The Duty Cycle really does depend on the ambient temperature as well. In Winter, the fridge will be on a fair bit less than in the Summer.
Looked at my fridge/freezer and it is running for around 30 minutes ever 2 Hrs 30 Mins (so around a 17% Duty Cycle).
When on around 5A, so around 20Ah/Day (and note this is a proper Fridge/Freezer with a separate 4* Freezer section with its own door)

Come summer, useage will be greater, but so will solar harvesting to compensate :)
 
My power consumption doesn’t seem to change much in the U.K. if it does it# by a very small margin
 
I only need a fridge in summer here as it freezing most of the year, I have a 4 point remote station and its 14.2 in the van 14.00 in the porch 15. loft and 22.5 in house. :)
 
My power consumption doesn’t seem to change much in the U.K. if it does it# by a very small margin
I do see a difference between summer and winter, and overnight vs a sunny day. This is usually with the van empty so more varience than maybe in your case with the motorhome much more in use?
 

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