Dometic CRX50 fridge problems

[Mike Woolstencroft]

Hi all

Wonder if anyone can help

Last week i noticed my freezer defrosted. So i checked the volts at the fuse box and at the back of the fridge both pretty much the same reading. Also cleaned the condenser not that it was that dirty. The fridge is (and has been for 2 and a half years) wired with 4mm cable and hasnt been too bad, i think ive always had it on setting number 3.

The fan and compressor seem to work, solid orange light when not on and blue light when the compressor is working, no flashing lights or anything.

I checked all the earths on the bus bar and at the fuse box and they all seem fine, but 1 which was tight enough but would turn a smidge so tighten it up. The thing is when it started playing up i would put the diesel heater on and after a short while the fridge would kick in.

I unplugged it from the power for about 20 mins to see if it would reset it and tried it again, everything froze again but then later at night it defrosted again, so i turned it up to setting number 4, it was on working for a few hours getting up to temp and everything seemed fine all day. then i went to work at 9pm and by 2am when i came back to the van (for lunch break) it was starting to defrost again. It was cold so i put the heating on and the fridge kicked in again. Then again it seems to work ok for the last couple of days kicking in and out (probably a bit too much but still its on and off)

I was wondering if the Thermistor or something was intermittent. but now i wondering whether my batteries aren't fully working. With the cold weather if i don't put the heater on for a bit and warm the battery compartment up they struggle to fully charge, even when warmed up the last 3/4% is slow. But my Victron B2B's are still charging so i'm not sure what's happenning. Hence me posting here to see if anyone might beable to help with any idea's

My batteries are 2 x 120A AGM's, i've got 2 30A Victron B2B's charging them. Usually lately when charged (from driving) they show 12.7/8.

I am this weekend going to be on mains hook up, so that might tell me a little more by the end of the weekend. If the fridge works all weekend as it should then yeah maybe it's my batteries dying, but i get no warning lights on the fridge....

Sorry for the long post but wanted to put as much info that i can remember (no doubt forgot something that will come to me later lol)

thanks in advance if anyone can help

 

[merl]

Hi all

Wonder if anyone can help

Last week i noticed my freezer defrosted. So i checked the volts at the fuse box and at the back of the fridge both pretty much the same reading. Also cleaned the condenser not that it was that dirty. The fridge is (and has been for 2 and a half years) wired with 4mm cable and hasnt been too bad, i think ive always had it on setting number 3.

The fan and compressor seem to work, solid orange light when not on and blue light when the compressor is working, no flashing lights or anything.

I checked all the earths on the bus bar and at the fuse box and they all seem fine, but 1 which was tight enough but would turn a smidge so tighten it up. The thing is when it started playing up i would put the diesel heater on and after a short while the fridge would kick in.

I unplugged it from the power for about 20 mins to see if it would reset it and tried it again, everything froze again but then later at night it defrosted again, so i turned it up to setting number 4, it was on working for a few hours getting up to temp and everything seemed fine all day. then i went to work at 9pm and by 2am when i came back to the van (for lunch break) it was starting to defrost again. It was cold so i put the heating on and the fridge kicked in again. Then again it seems to work ok for the last couple of days kicking in and out (probably a bit too much but still its on and off)

I was wondering if the Thermistor or something was intermittent. but now i wondering whether my batteries aren't fully working. With the cold weather if i don't put the heater on for a bit and warm the battery compartment up they struggle to fully charge, even when warmed up the last 3/4% is slow. But my Victron B2B's are still charging so i'm not sure what's happenning. Hence me posting here to see if anyone might beable to help with any idea's

My batteries are 2 x 120A AGM's, i've got 2 30A Victron B2B's charging them. Usually lately when charged (from driving) they show 12.7/8.

I am this weekend going to be on mains hook up, so that might tell me a little more by the end of the weekend. If the fridge works all weekend as it should then yeah maybe it's my batteries dying, but i get no warning lights on the fridge....

Sorry for the long post but wanted to put as much info that i can remember (no doubt forgot something that will come to me later lol)

thanks in advance if anyone can help

It's probably because the ambient temperature is so low at the moment.
If the thermostat is located in the fridge section then with an ambient temperature of just a few degrees above freezing the stat will hardly ever 'call' . Hence the unit rarely kicks in and hence the freezer doesn't get activated because it's on the same compressor as the fridge.
The upshot is you have to have a warm van to get a cold freezer

 

[Mike Woolstencroft]

Possibly But past winters its been ok. I must admit i don't sleep with the heater on so it can be between 2 and 9 degrees inside the van during the night. but usually it does kick in sometimes.
Just not good at the moment as my freezer stuff keeps defrosting (obviously not going to eat it, its just there to keep a check on things lol) and the fridge isn't even cold. As you say its definately not being called upon to be kick started.

 

[merl]

It's been particularly cold recently hovering just above freezing point so you probably didn't encounter this exact scenario before and you may have reacted differently to it too? It may well have previously been behaving ALMOST AS POORLY as it is currently but the freezer food remained ONLY JUST frozen and you never realised it was actually way too warm. If you've not got a thermometer in the freezer which you monitor then you're only guessing at what's going on and indeed what has happened previously and you could easily get mislead.
Turn the heating up and I'll bet all will resume to normal

 

[Exwindsurfer]

It's been particularly cold recently hovering just above freezing point so you probably didn't encounter this exact scenario before and you may have reacted differently to it too? It may well have previously been behaving ALMOST AS POORLY as it is currently but the freezer food remained ONLY JUST frozen and you never realised it was actually way too warm. If you've not got a thermometer in the freezer which you monitor then you're only guessing at what's going on and indeed what has happened previously and you could easily get mislead.
Turn the heating up and I'll bet all will resume to normal

I'll second that as I have the 110ltr compressor ans it does the same when it gets to cold outside

 

[wildebus]

It's been particularly cold recently hovering just above freezing point so you probably didn't encounter this exact scenario before and you may have reacted differently to it too? It may well have previously been behaving ALMOST AS POORLY as it is currently but the freezer food remained ONLY JUST frozen and you never realised it was actually way too warm. If you've not got a thermometer in the freezer which you monitor then you're only guessing at what's going on and indeed what has happened previously and you could easily get mislead.
Turn the heating up and I'll bet all will resume to normal

I would guess that is likely to be the issue. Same as when you run a fridge or freezer in an unheated garage and it stops working on very cold days as it is too cold.

On the other point raised which you reply to, it is very common - and undesirable - for the freezer sections to nearly defrost, refreeze, and then repeat. My Waeco CRX50 used to do that sometimes.
I recommend getting something like this - https://amzn.to/41c1k71 - for both the fridge and the freezer. It will give you minute by minute temp info and tell you how well your fridge is actually working.

 

[wildebus]

I'll second that as I have the 110ltr compressor ans it does the same when it gets to cold outside

Not too useful really. I don't have these issues with my (240v) Compressor Fridge/Freezer, but might be that I bypass the integral fridge thermostat so the fridge itself doesn't control anything? The chart below shows the Freezer behaviour hasn't really changed (except possibly getting slightly colder at the coldest room temp?)

 

[Exwindsurfer]

I am tempted to put a domestic 240v larder fridge in and do away with the freezer bit David .

 

[wildebus]

I just emptied the last bit of food from my Fridge and Freezer out the Motorhome (no point in leaving it running when little in it) .... the fridge has dropped down to -2C! I think it went low because the room temp is so low (only 2C below ambient )

 

[Mike Woolstencroft]

It's been particularly cold recently hovering just above freezing point so you probably didn't encounter this exact scenario before and you may have reacted differently to it too? It may well have previously been behaving ALMOST AS POORLY as it is currently but the freezer food remained ONLY JUST frozen and you never realised it was actually way too warm. If you've not got a thermometer in the freezer which you monitor then you're only guessing at what's going on and indeed what has happened previously and you could easily get mislead.
Turn the heating up and I'll bet all will resume to normal

I have in the past noticed the freezer defrosting although it was only minor, this just threw me as its multiple times in totally defrosted to the point where theres not much ice left in the freezer.
Will keep an eye on it for a while then, and just mainly use the fridge for now

 

[Mike Woolstencroft]

I would guess that is likely to be the issue. Same as when you run a fridge or freezer in an unheated garage and it stops working on very cold days as it is too cold.

On the other point raised which you reply to, it is very common - and undesirable - for the freezer sections to nearly defrost, refreeze, and then repeat. My Waeco CRX50 used to do that sometimes.
I recommend getting something like this - https://amzn.to/41c1k71 - for both the fridge and the freezer. It will give you minute by minute temp info and tell you how well your fridge is actually working.

Will have a look around for something like that, see what its actually doing. As half the time the fridge stuff doesnt seem that cold, although the freezer normally does work ok and keep things frozen.

 

[Exwindsurfer]

Will have a look around for something like that, see what its actually doing. As half the time the fridge stuff doesnt seem that cold, although the freezer normally does work ok and keep things frozen.

I've noticed with the latest CRX fridges you can take the freezer box out and just use it as a fridge wish I had that option with my 110ltr Weaco.

 

[cheyenne]

i am glad we have the 3 way fridge instead of a compressor fridge no problems we ours now touring Spain in 35ceg plus & we can take the freezer door/shelf out to make one big fridge .cheyenne

 

[Mike Woolstencroft]

Been thinking about this, and the last couple of days it seems to be ok as far as i can tell its not defrosting.

But my thermostat is inside the fridge would the outside temp really affect whats going on inside that much. I thought if the fridge was going warmish inside the fridge would kick in?

 

[wildebus]

I've noticed with the latest CRX fridges you can take the freezer box out and just use it as a fridge wish I had that option with my 110ltr Weaco.

This was one of the key changes when the CR became the CRX. Can be used as a Fridge or a Freezer rather than a Combo. (I had considered getting 2 x CRX-50s and stacking them for this flexibility before I went for the option I did).

i am glad we have the 3 way fridge instead of a compressor fridge no problems we ours now touring Spain in 35ceg plus & we can take the freezer door/shelf out to make one big fridge .cheyenne

Yes, the 3-ways are far better and more reliable, aren't they?

(wanna buy a bridge? got one going cheap )

 

[Exwindsurfer]

I've been using one of these for a year or so works fine

 

[Exwindsurfer]

Mike this is what my fridge freezer is running at now

 

[Mike Woolstencroft]

Thanks

Think getting one of those is the way to go. Least then i will have an idea of what the temp is inside at random point of the day and depending on what the weather is like. As it hasn't been getting (or keeping) as cool as it should despite the thermostat being inside the fridge

Thanks for the recommend

 

[wildebus]

I've been using one of these for a year or so works fine View attachment 70760

Is that just a Min/Max or does it log throughout time?

If if is just Min/Max, you won't see the full pattern of freeze/defrost, especially if you don't check every day.
The reason why I like the ones I linked to is that you get a constant picture of the temperature pattern throughout an extended time period (2 weeks or more) on a minute by minute basis so you are not locked into having to check everyday.
You can also connect via Bluetooth or Wifi via an App and save the data if you want to cross-reference or keep a record.

 

[cheyenne]

Thanks

Think getting one of those is the way to go. Least then i will have an idea of what the temp is inside at random point of the day and depending on what the weather is like. As it hasn't been getting (or keeping) as cool as it should despite the thermostat being inside the fridge

Thanks for the recommend

we have these just as good & cheaper . cheyenne

https://www.amazon.co.uk/Thermometer-Refrigerator-INRIGOROUS-Stainless-Retractable/dp/B07PCLJZW4/ref=asc_df_B07PCLJZW4/?tag=googshopuk-21&linkCode=df0&hvadid=309950300069&hvpos=&hvnetw=g&hvrand=9233441933931954318&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006918&hvtargid=pla-662982829140&mcid=ea84108bbfdb35599c28a6507b59082c&th=1