AC Fridge In Campervan -.Power Consumption Test

[trevskoda]

Trev, I am sure they do as does everyones in their vans. I meant it as a test to determine what wakes the Inverter up.

For example, I have set up my inverter so it wakes up when the Fridge Compressor starts but it won't wake up when the fridge door is opened and the little light comes on....

No light in my fridge so that old myth goes out the window,will do test to see what wakens inverter tomorrow,il start with a 10w led work light.

 

[wildebus]

that old myth? what old myth is that?

 

[trevskoda]

that old myth? what old myth is that?

That the light goes out when you close the door,no one really knows.

 

[wildebus]

That the light goes out when you close the door,no one really knows.

Oh right. Actually I know it does as my monitoring system will show me the extra 6W the bulb uses
(Compressor Fridges are so efficient that if the bulb DID stay on with the door closed, the total power consumption would likely double!)

 

[trevskoda]

To days test will be to remove the battery charger which is putting in about same as solar,then i can find out if fridge will run over night without killing the batterys of sending the inverter into shut down mode which requires a man/start.

 

[RV2MAX]

Have read thru most of this thread , very interesting and informative on a tech level . I have been running a double door domestic fridge freezer thru inverter in my RV , for a couple of years now . Just wanted to raise one point , that doesnt seem to have been covered , and that is not all (most) are not rated for external use. I under stand this in relation to thermostats getting tricked. I have a suitable rated unit , and still have the external venting so no heat transfer to interior when high temps , so when it works most . I would suggest that if you are using a domestic unit in a MoHo with external vents , that they be shut off in winter conditions

 

[wildebus]

Have read thru most of this thread , very interesting and informative on a tech level . I have been running a double door domestic fridge freezer thru inverter in my RV , for a couple of years now . Just wanted to raise one point , that doesnt seem to have been covered , and that is not all (most) are not rated for external use. I under stand this in relation to thermostats getting tricked. I have a suitable rated unit , and still have the external venting so no heat transfer to interior when high temps , so when it works most . I would suggest that if you are using a domestic unit in a MoHo with external vents , that they be shut off in winter conditions

This is a good point. I know many fridges and freezers are classifed as not suitable for use in a Garage due to the low temperatures that can be experienced, and the temperture range inside a campervan/motorhome is probably wildly varying compared to the average house. The Fridge I bought is stated as Domestic Use only I think (but all 240V consumer items would be I'd imagine?)
This was something that I was curious to know - how well mine would cope compared to a "proper" RV fridge and to date there have been no issues. It has had the same range of external (to Fridge) temps to deal with - from below 0C to 50C - as the Weaco CRX-50 before it and it has worked just as well. I've no external venting in my van, being a conversion but to deal with the higher compressor temps, I have fitted a fan and sensor so some air does blow at the compressor (although when it was around 50C the whole van was that temp so it didn't cool it but still worked fine).

I don't believe there is any more significant heat transfer into the fridge when the van is at a high temp compared to a 12V DC RV Fridge (at least the one I had). I had until recently an "In/Out" thermometer in the fridge and the range of internal temp didn't fluctuate that much and no more than the CRX-50 did. Sure it was not precise and stayed within 1 degree of a setting like maybe some Medical Lab Fridge might, but it stayed within the same range as any fridge I have used, mobile or fixed.

What kind of power does your Fridge Freezer use? When I was looking at options I would have liked a Fridge-Freezer but the extra power useage due to the demands of a genuine dual compartment Fridge Freezer (as opposed to a Fridge with an Ice box) was more than I really wanted to deal with (my target being to match something like a Weaco CR-80 in size and power) and the best I could find had a power usage around 50% greater than the 93L Fridge I went with.

 

[RV2MAX]

This is the unit I have , I haven't paid much attention to the consumption , as I have 900w of solar and 450ah batteries ,
if I was to get low on power , there is a onboard 6.5 kva lpg gennie . It does seem to be quite good , as my batteries don't seem to cycle much in voltage (charge) level .
https://www.beko.co.uk/frost-free-combi-fridge-freezer-cfg1552-black-silver-white , you might be able to get tech info there
BTW what ariston unit is that in your build ?

 

[wildebus]

This is the unit I have , I haven't paid much attention to the consumption , as I have 900w of solar and 450ah batteries ,
if I was to get low on power , there is a onboard 6.5 kva lpg gennie . It does seem to be quite good , as my batteries don't seem to cycle much in voltage (charge) level .
https://www.beko.co.uk/frost-free-combi-fridge-freezer-cfg1552-black-silver-white , you might be able to get tech info there
BTW what ariston unit is that in your build ?

It is this chap - https://www.screwfix.com/p/ariston-undersink-water-heater-2kw-10ltr/3248g#_=p

I would have liked a lower power element to the 2kW but not able to find one (pulling 200A from the Battery Bank is not ideal but having said that it only takes around 7 Running Minutes to raise the temp to the ECO (~60C) level).

 

[trevskoda]

Well as from early 8am to just now 7pm my fridge has been working of batts with no charger linked up in w/shop at 8c,batts still showing 12.2v and these are old truck 90ah open vent wet l/A.
So my thinking is in summer at 25c they will easy go from sun down to dawn which is at best 4/5 hrs where i may start to get at least 1ah starting to flow back into battery,or i can start the engine if required though i dought it whilst getting the porridge on.

 

[trevskoda]

Ok went out to w/shop at 7.30am this morning and batterys still holding at 12.1v and fridge / inverter still on song,im leaving charger of to see how long all will work before inverter trips,so far 24hrs running time.

 

[trevskoda]

Well out tonight after another 12 hrs with no charge and the fridge and inverter still working,but batterys down to 11.8v so to not kill them i have now started to recharge them.
Well what i found was same as wildbus that compressor fridge is just fine in a van and can easy go 36 hrs but i would think in summer not so long,so in short a over night with maybe tv and a led light you should have no bother winter or summer,though maybe if a diesel blow heater is being used then unless 2 good or more batterys over 200ah you may be on the edge.

 

[wildebus]

My running and data logging over around 16 months, including very cold weather and the heatwave we had last summer tells me that an increased interior van temp does not make that much difference to the energy consumption of a fridge. Yes, it will be greater but not dramatically so and I really think anyone with solar would be able to run 24/7 in the summer. (This does assume the fridge door is only opened occasionally - if you have people who are constantly opening the door for stuff then the difference will be greater).

 

[trevskoda]

Yes you will be spot on,this is now going to be fitted as im well pleased and thank you wildbus for taking time to post info which helped no end.

 

[wildebus]

Yes you will be spot on,this is now going to be fitted as im well pleased and thank you wildbus for taking time to post info which helped no end.

No worries. It is interesting to see feedback on an A+ fridge rather than my own A++. I would have expected worse results TBH so it is very promising what you are getting
And .... it is making me wonder how feasible it will be to bring in my little Tabletop Freezer (currently a kitchen "Overflow" Freezer) into the van on occasions in fact! That could be very handy if going away in the summer to a festival and want a good supply of ice cubes and ice creams .
I might have to do a wee test on what power that sucks

 

[trevskoda]

No worries. It is interesting to see feedback on an A+ fridge rather than my own A++. I would have expected worse results TBH so it is very promising what you are getting
And .... it is making me wonder how feasible it will be to bring in my little Tabletop Freezer (currently a kitchen "Overflow" Freezer) into the van on occasions in fact! That could be very handy if going away in the summer to a festival and want a good supply of ice cubes and ice creams .
I might have to do a wee test on what power that sucks

Dont mention ice creams or you may have an extra passenger.

 

[linkshouse]

trevskoda, can I just confirm that this is the inverter you bought - https://www.ebay.co.uk/itm/NIKKAI-Power-Inverter-DC-to-AC/113301616746?_trksid=p2485497.m4902.l9144

The reason that I ask is that their description specifically says not for inductive loads, which is what a fridge is.

That said this is a good price and if it works in practice with your real-world example that's good enough for me.

 

[trevskoda]

trevskoda, can I just confirm that this is the inverter you bought - https://www.ebay.co.uk/itm/NIKKAI-Power-Inverter-DC-to-AC/113301616746?_trksid=p2485497.m4902.l9144

The reason that I ask is that their description specifically says not for inductive loads, which is what a fridge is.

That said this is a good price and if it works in practice with your real-world example that's good enough for me.

Yes go for it,i have had mine stored for a few years as bought from a shop closing down £25 then.

 

[Duckato]

My smaller Inventer is in situ now in my ex A&E Sprinter Ambulance I have the larger 93L for my VW Crafter but build has slowed a bit on that van, I am having too much fun playing with the Sprinter!

I probably will be leaving it running 24x7 as a pre camping soak test once I have the auxiliary batteries permanently installed.

 

[Duckato]

I have a bit of an issue to report
My A++ Inventor fridge does not seem to be getting on too well with the Victrons ECO mode.
I have noticed on several occasions that when the fridge is calling for power the brief spike from the inverter when polling for the load starts the compressor for a fraction of a second then there is a pause for a few more seconds before the power comes on as the inverter reacts to the demand.

That seems to be upsetting my compressor, it stalls and I see 30A being drawn from the battery for about a minute or so then there is a click and the fridge gives up and stops drawing power. This cycle is continuous and the compressor seems to stall about 1 time in 10

This only happens in ECO mode, at the moment the Inverter is set to Victrons defaults and polls every 3 seconds I might change that to once a minute and see what happens but right now the only way it works reliably for me is with ECO off.