AC Fridge In Campervan -.Power Consumption Test

[wildebus]

Interesting. When I first looked at this setup I thought it wouldn't work with ECO mode (can't recall the reason now) but when I got round to trying it later it seemed fine.
What inverter size do you have? the inrush spike on the fridge is close to the surge limit of the 12/500 400W inverter. I wonder if the slight delay in the inverter going on from detecting demand is creating a larger spike that cannot be accomodated?

 

[Duckato]

I have the Victron 12/500 same as yours I also have two inventer fridges the smaller 40L and the larger 93L I have only been testing the smaller fridge so far.
I may swap over to the larger one and see if it behaves, I may actually have a faulty compressor!

 

[wildebus]

I have the Victron 12/500 same as yours I also have two inventer fridges the smaller 40L and the larger 93L I have only been testing the smaller fridge so far.
I may swap over to the larger one and see if it behaves, I may actually have a faulty compressor!

I would have thought bad compressor as well but that doesn't fully explain why all is ok on no-ECO mode (unless it is like I said about the spike is a symptom of a sticky compressor?
What you are describing is quite common with Air-Con Units I think and people fit Soft-start kits to make the starting a lot more gentle (I have one but couldn't see a way to fit it to the Fridge compressor)

 

[Duckato]

Well I can confirm 100% that my smaller Inventor fridge does not like the Eco mode.
I left it running overnight on normal and it was fine but this morning as soon as I switched the inverter to eco it stalled almost constantly, this may well be a symptom of excess inrush current because I also get a high voltage alarm (again only on eco mode) so I think for this particular fridge the 12/500 is not up to it.

On the Victron site another owner seems to be having similar issues with a Liebherr TP 1720 and that seems even more efficient than the Inventors.

I also think the Victron Windows app is a bit limited as well!
Zero logging or history available all I see is a round circle with bars lit up dependent on load, nothing like in the pictures Victron provide online showing a bar graph over time at the bottom so I can't even capture how often the compressor does stall.

I will still try it against my 93L inventor later on, sods law says the big fridge will be fine unfortunately that's not the one I want to use in this particular van at this time!

 

[wildebus]

Well I can confirm 100% that my smaller Inventor fridge does not like the Eco mode.
I left it running overnight on normal and it was fine but this morning as soon as I switched the inverter to eco it stalled almost constantly, this may well be a symptom of excess inrush current because I also get a high voltage alarm (again only on eco mode) so I think for this particular fridge the 12/500 is not up to it.

On the Victron site another owner seems to be having similar issues with a Liebherr TP 1720 and that seems even more efficient than the Inventors.

I also think the Victron Windows app is a bit limited as well!
Zero logging or history available all I see is a round circle with bars lit up dependent on load, nothing like in the pictures Victron provide online showing a bar graph over time at the bottom so I can't even capture how often the compressor does stall.

I will still try it against my 93L inventor later on, sods law says the big fridge will be fine unfortunately that's not the one I want to use in this particular van at this time!

Interesting to hear this. I think the power specs between the two fridges are the same but could have been a copy and paste job by the makers as the difference is not that important for most people.
I would think the 12/800 (700W) inverter would be ok? It must be really borderline if only happens in Eco Mode?

The logging on the Pheonix inverters is not very good even though the inverters themselves are excellent. The Inverters which have a VE.Bus connection are much better. This is what I logged with the Multiplus-II 12/800 running the bigger Inverter 93L fridge.


MP800-FridgeACvsOverload by David, on Flickr
you can see the overload situation everytime the Compressor kicks on (so load >700W).

 

[Duckato]

I have now tested this with effectively two identical fridges (both mine do have the same compressor) just in case on of them was faulty both compressors stall randomly on Eco mode using the Phoenix 12/500 Inverter, and both trigger high voltage alarms when stalled.

I am now in the difficult position of do I risk wasting another £100+ on the next model up the 12/800 only to find that's no good either! I think the answer to that is no it is not worth the risk.

I will (try to) return my Phoenix for a refund and buy a cheaper more powerful sine wave based inverter instead from elsewhere.

As an aside I have another inverter from one of my ex Ambulances a Sterling Power 1800 Quasi sine wave variant which I have also done some tests on before ruling it out as well.

The modified sine wave is not efficient, surprisingly so with inductive loads, the fridge draws approx 40 watts on the pure sine wave Phoenix but > 55watts on the Sterling power one!

however with a resistive load a 100W light bulb the wattage was less

 

[wildebus]

Interesting stuff. I know as you go up the power within the Victron Range, the prices do tend to increase exponentially!
I wonder if your inverter is faulty? I think it is worth while getting it checked into.

For alternatives, maybe look at the Edecoa range available through Amazon? They are well made, very quiet in use and reasonably priced.
I had the 2500W EDEOCA PSW inverter. It did fail after about 10 month, but any product can fail so I was not that concerned for the brand as a whole (and I got a full refund for it on return as well) and in fact just bought another EDECOA a few days ago - 1500W Pure Sine Wave for £175 which I think is pretty good. Not cabled it up yet (for a customer install I am doing) but I am expecting good things from it
This is the 1000W unit version - https://amzn.to/2ETNCgi - but that is only £30 cheaper (think the 1500W for £175 seems better value?).
The inverters from this brand tend to be quite large physically as they use the casing with lots of vanes for primary cooling I think (but upside from the size is the quiet running (being quiet is very important for me personally - can't be doing with a fan running all the time).

 

[mistericeman]

Interesting stuff. I know as you go up the power within the Victron Range, the prices do tend to increase exponentially!
I wonder if your inverter is faulty? I think it is worth while getting it checked into.

For alternatives, maybe look at the Edecoa range available through Amazon? They are well made, very quiet in use and reasonably priced.
I had the 2500W EDEOCA PSW inverter. It did fail after about 10 month, but any product can fail so I was not that concerned for the brand as a whole (and I got a full refund for it on return as well) and in fact just bought another EDECOA a few days ago - 1500W Pure Sine Wave for £175 which I think is pretty good. Not cabled it up yet (for a customer install I am doing) but I am expecting good things from it
This is the 1000W unit version - https://amzn.to/2ETNCgi - but that is only £30 cheaper (think the 1500W for £175 seems better value?).
The inverters from this brand tend to be quite large physically as they use the casing with lots of vanes for primary cooling I think (but upside from the size is the quiet running (being quiet is very important for me personally - can't be doing with a fan running all the time).

I've got a very similar 3000w mod sine one in the transit (branded Spannungswandler)
Probably out of the same parent company by looks AND by the remote panel...
Can't complain at the cost (£170 ish) including remote and powered our microwave /kettle/toaster/slow cooker etc without issue.

 

[wildebus]

"Spannungswandler" is just the German term used for an Inverter, so you will see quite a few with that label kicking around

 

[SquirrellCook]

My bum is numb after spending a good few hours reading though it. I wish I had the funding and ability that you've clearly had. In the early days I had luck, but it turns out I was mislead by it.
Having ruined to much good food with a 3 way fridge I needed a better solution. Yes I know they don't work well whilst driving, but it had too.
The first lead into the unknown was around 10 years ago. I purchased a cheap under counter fridge "Husky" I had a small 200watt inverter. Previously used for running computer monitor from 12 volts. Heavy glass CRT versions. A friend donated a pile of ex UPS 6volt bricks. Luckily I found 2 good ones. Summer testing in closed bus, around 7 days run time for the fridge without disturbing it. For around a year all worked well, until one hot night we were rudely awoken by a very load bang and a smoke filled bus. Many inverters were purchased to start the fridge and we ended up with a 600 watt one that would just about start it. Run time was just over a day with the new inverter. Must be a duff fridge. So each time the old fridge was sold to by a new higher spec replacement. The fridge we have now is the hardest to start and most expensive, though reading your numbers were seeing about the same summer consumption. Hard start devices were tried and many other gimmicks. None worked. The journey into solar was only to keep the fridge running for longer without a generator or hookup. Fed up with poor functioning and low life inverters we installed a Victron 12/800 and though it coughs a little on some starts it's been doing well for two years. Charge controllers also bothered me as the displays of performance seemed fictional, and I now believe it was. From limited experience, they seem to be sunshine meters. Having changed over the again a Victron 30amp charge controller the improvements are shocking. This is a Bluetooth version so observed from my phone. Unless you observe the off load PV voltage it is no longer a sunshine meter. There are other ways to tell if it's sunny! If it's not loaded it appears to give poor results. When it's sunny and you've hammered your poor batteries you really get to see how well it works. I still feel that a 12 volt compressor fridge should be the best, though watch out as some appear to be 240volt ones with inverters built in. Again funding won't allow testing. If I had a good mate who was a refrigeration engineer I expect a 12 volt Danfoss compressor would be the way to go. That said, if I had a problem with my 240 volt fridge in Europe, it shouldn't be hard or expensive to replace it. Again well done in hard work putting this together. It should save a lot of people wasting money on the tall tales of salesmen.

Mark

 

[Squiffy]

I really dont understand Mark, I have used 3 way fridges for years and years too many for me to contemplate and have never had a destroyed food situation, can you explain how you have had this situation happen to you on what seems to be many occasions according to your post. Phil

P.s. I have also travelled on 12volt (13.6volt) for 48hrs in the past and still have had an acceptable low tempreture when parked up.

P.P.s
I don't decry the electrical advance that is being made and think that it must be the future, but I don't believe the horrors of 3 way fridges if installed and kept serviced correctly

 

[mistericeman]

"Spannungswandler" is just the German term used for an Inverter, so you will see quite a few with that label kicking around

I know mate .....
Point I was trying to make was that there are a lot of units around that likely originate in a single factory BUT have different coloured casings/names etc etc (sometimes a good thing.... Sometimes a bad thing lol)

This is the one I have (12v 3000w)

View attachment 1386View attachment 1386

My bum is numb after spending a good few hours reading though it. I wish I had the funding and ability that you've clearly had. In the early days I had luck, but it turns out I was mislead by it.
Having ruined to much good food with a 3 way fridge I needed a better solution. Yes I know they don't work well whilst driving, but it had too.
The first lead into the unknown was around 10 years ago. I purchased a cheap under counter fridge "Husky" I had a small 200watt inverter. Previously used for running computer monitor from 12 volts. Heavy glass CRT versions. A friend donated a pile of ex UPS 6volt bricks. Luckily I found 2 good ones. Summer testing in closed bus, around 7 days run time for the fridge without disturbing it. For around a year all worked well, until one hot night we were rudely awoken by a very load bang and a smoke filled bus. Many inverters were purchased to start the fridge and we ended up with a 600 watt one that would just about start it. Run time was just over a day with the new inverter. Must be a duff fridge. So each time the old fridge was sold to by a new higher spec replacement. The fridge we have now is the hardest to start and most expensive, though reading your numbers were seeing about the same summer consumption. Hard start devices were tried and many other gimmicks. None worked. The journey into solar was only to keep the fridge running for longer without a generator or hookup. Fed up with poor functioning and low life inverters we installed a Victron 12/800 and though it coughs a little on some starts it's been doing well for two years. Charge controllers also bothered me as the displays of performance seemed fictional, and I now believe it was. From limited experience, they seem to be sunshine meters. Having changed over the again a Victron 30amp charge controller the improvements are shocking. This is a Bluetooth version so observed from my phone. Unless you observe the off load PV voltage it is no longer a sunshine meter. There are other ways to tell if it's sunny! If it's not loaded it appears to give poor results. When it's sunny and you've hammered your poor batteries you really get to see how well it works. I still feel that a 12 volt compressor fridge should be the best, though watch out as some appear to be 240volt ones with inverters built in. Again funding won't allow testing. If I had a good mate who was a refrigeration engineer I expect a 12 volt Danfoss compressor would be the way to go. That said, if I had a problem with my 240 volt fridge in Europe, it shouldn't be hard or expensive to replace it. Again well done in hard work putting this together. It should save a lot of people wasting money on the tall tales of salesmen.

Mark

As a fridge/aircon engineer I considered converting a, 240 fridge to 12v compressor....
Even with my skill set and qualifications I still ended up buying a 40l Waeco....

And ill be buying a waeco replacement for the 3 way in the motorhome ASAP.

 

[wildebus]

It is the desire to not give salesmen lots of money to purchase goods which are no better than fairly common household items that led me to this pathway - and a way to NOT use a big budget I don't have.

80+L 12V compressor fridge ... £800+
80+L 3-way Fridge ... £1,000+
93L 240V Fridge... £170

Gas Hob .... £200+
My Electric Induction Hob ... £20

Hot Water Heater ... £140 Inc all plumbing. "Proper" Motorhome fridge ... Quite a few hundreds I believe?

It is easy to end up spending loads on stuff you are told you must have, so if my ramblings have saved some folk some cash that is good

 

[SquirrellCook]

I really dont understand Mark, I have used 3 way fridges for years and years too many for me to contemplate and have never had a destroyed food situation, can you explain how you have had this situation happen to you on what seems to be many occasions according to your post. Phil

P.s. I have also travelled on 12volt (13.6volt) for 48hrs in the past and still have had an acceptable low tempreture when parked up.

P.P.s
I don't decry the electrical advance that is being made and think that it must be the future, but I don't believe the horrors of 3 way fridges if installed and kept serviced correctly

This was many years ago with the fridge mounted in the front foot well of a Mercedes 608 LWB I'm sure the fridge was tired as well. Whilst in motion it required 12 volts and gas to keep it cool. The Merc had a wonderful air vent to cool it's back as well. Didn't want to work on uneven ground. Sometimes it would not work at all unless it was removed from the vehicle and rolled around a few times. I'm sure they are better now. That said we often hear stories of fridges not working well enough when it's silly hot.

Mark

 

[SquirrellCook]

I know mate .....
Point I was trying to make was that there are a lot of units around that likely originate in a single factory BUT have different coloured casings/names etc etc (sometimes a good thing.... Sometimes a bad thing lol)

This is the one I have (12v 3000w)

View attachment 1386View attachment 1386


As a fridge/aircon engineer I considered converting a, 240 fridge to 12v compressor....
Even with my skill set and qualifications I still ended up buying a 40l Waeco....

And ill be buying a waeco replacement for the 3 way in the motorhome ASAP.

From the research I've done it does seem like a lot to change other than the compressor, that said I've seen reports of the simple route being taken and it working well, though technically wrong. I must admit as I get older, sometimes it's easier just to throw money at a problem.

Mark

 

[SquirrellCook]

It is the desire to not give salesmen lots of money to purchase goods which are no better than fairly common household items that led me to this pathway - and a way to NOT use a big budget I don't have.

80+L 12V compressor fridge ... £800+
80+L 3-way Fridge ... £1,000+
93L 240V Fridge... £170

Gas Hob .... £200+
My Electric Induction Hob ... £20

Hot Water Heater ... £140 Inc all plumbing. "Proper" Motorhome fridge ... Quite a few hundreds I believe?

It is easy to end up spending loads on stuff you are told you must have, so if my ramblings have saved some folk some cash that is good

I'm waving the flag, it does work. What's needed is this kind of guidance. Trying to do it cheaply with no valid help has cost me around £2000. But I'm more experienced now

Mark

 

[trevskoda]

This one works on mine

 

[Duckato]

An update from victron so my 12/500 is going back for a refund not only because it isn't man enough for the job but because it makes a horrid buzz (transformer hum) as well every time the fridge starts.

"Victron have advised that there is no defect with your inverter and that, regardless of the make, inverters will not start a fridge compressor when in Eco mode."

I also have another slightly more powerful pure sine wave inverter and that also fails to start the compressor occasionally so clearly for this experiment to work requires using a much more powerful inverter than I had ever expected with the knock on effect of waste energy from it being on and idling most of the time.

Once I have my refund I will buy yet another one and hopefully I will be third time lucky

Swmbo is not impressed and an alternative 12v fridge may be bought now instead.

 

[Duckato]

Onboard Energy have just informed me they will kindly charge me a minimum 25% restocking fee for the privilege of returning this not fit for purpose inverter!

This damn exercise is starting to get bloody expensive now!

I will probably lose less money putting it on eBay!

I would put up with it if it weren't for the annoying loud buzz it makes ever time the fridge starts up.

 

[wildebus]

An update from victron so my 12/500 is going back for a refund not only because it isn't man enough for the job but because it makes a horrid buzz (transformer hum) as well every time the fridge starts.

"Victron have advised that there is no defect with your inverter and that, regardless of the make, inverters will not start a fridge compressor when in Eco mode."

I also have another slightly more powerful pure sine wave inverter and that also fails to start the compressor occasionally so clearly for this experiment to work requires using a much more powerful inverter than I had ever expected with the knock on effect of waste energy from it being on and idling most of the time.

Once I have my refund I will buy yet another one and hopefully I will be third time lucky

Swmbo is not impressed and an alternative 12v fridge may be bought now instead.

"Victron have advised that there is no defect with your inverter and that, regardless of the make, inverters will not start a fridge compressor when in Eco mode."
As I mentioned, I found the Eco mode wasn't liked when I first tried it, but when I tried later on, it did work - maybe the compressor needed to loosen up? I was running my 12/500 in Eco mode I am sure for most of the time. I am certainly running my Multiplus in AES mode (which is the MP version of Eco) and it wakes up when the fridge wants power - but the Multiplus IS a much more intelligent device so they may be differentiating ECO and AES which would be fair enough.

The buzz when the fridge starts up - that will be the inverter going into the overload situation. the 12/500 is a 400W inverter and you are calling on around 800W of power to start the compressor. The inverter is designed to cope with short periods of overload upto 900W but it does make that kind of buzz/jolt each time. Same happens with the Multiplus 12/800 (700W Inverter) as that overloads. Call it a 'feature', call it annoying, but I wouldn't call it a fault.

The In-Rush power surge from the compressor is a pain no doubt as it means the inverter has be sized way way bigger than the normal power needs of the fridge when running.

Talking bigger money here and it is not a saving if the only objective is to save money on a 12V fridge, but this kind of product would run the fridge without any overloading and provide loads of extra features .... http://www.onboardenergydirect.co.u...us-Inverter-Charger-12-1200-50-16.html#SID=40

• 2400 Watts Peak Power
• 1000Watt / 1200 VA Continuous

Or this straight inverter that offers the same power rating for around £350, so you would still save on 240V + Inverter combo over a 12V Compressor Fridge - http://www.onboardenergydirect.co.u...erter--12-1200-IEC.-VI12_1200_IEC.html#SID=36

Both the above are Victron I accept and so are not the cheapest available by any means. Each to their own, but if I am having an inverter powered up (even in an Eco type mode) 24/7 and unattended, I want a product I can trust and believe in, and one that is generally silent in operation. There are loads of Inverters out there; Most of them are pretty poor TBH and I would not want to leave running constantly.
I sell a few cheap inverters to folk who want to be able to plug in their laptop to charge, or random things and those cheapies are fine for the limited use they are put to, but if someone bought one of those and said they intended to run their fridge on it for ever, I would suggest they invest in better quality for numerous reasons.

As an aside, something I looked at - and actually bought a kit from the US to see if I could fit it - was a Hard Start kit. These are fitted to domestic Aircon units as I undertand it (misterriceman would likely know a lot more on this) and eliminate the inrush by using stored energy in a big capacitor instead. One of these - if they could be fitted - would likely mean a super-small inverter could be used?
I couldn't see how to fit in on the fridge and as fridges/aircon compressors are not my bag I just left is as it was as the savings were more than enough to run with the inverter I selected.
(I stil have this Hard Start Kit, unopened and unused, if anyone fancies trying to fit it?)