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Hi, please can anyone help me confirm the air sensor for my fridge-freezer and how to fit it? I got some online advice from justanswers.com but he’s reached the limit of his knowledge.
The background is that the f/f (upright with the fridge on top) started to get too cold, with ice forming on the bottom of the crisper and freezing the veg. The engineer on justanswers said the air sensor was the most likely cause, which is in the freezer, and permanently wired through the insulation. (I was about to replace the control board and potentiometer assembly in the top of the fridge compartment, but this is apparently more stable.)
The problem is that the pictures of the air sensor I’m finding online don’t look like the thing in the back of the freezer. They have a thin black object at the end of the wire, where the only thing permanently wired through the freezer housing ends in a thicker white cylinder, attached to either the evaporator tubing or perhaps the heater element next to it. It can be seen in this photo of my freezer. I’m not sure it’ll embed, so the download link follows.
The engineer sent me a pdf document about replacing the part, which you can also download from here. It mentions an air sensor and an evaporator sensor, the latter having a “big insulator”. But it’s also confusing, as it seems to be talking about a modification with a before and after photo, as well as replacing either sensor.
I copied the part number of the air sensor, did a search and found it in various places, including here at ukwhitegoods. This page also mentions the evaporator sensor with its large insulator, also available.
So that’s where I’m upto. I don’t understand why the black thing isn’t the same as the white cylinder in my freezer. I don’t know whether the replacment fits inside the white thing, or if I just replace one for the other, or if this is even the right part. I don’t understand whether my freezer has both an air sensor and an evaporator sensor (another part looking very like the photos of the sensors on sale is fixed to the evaporator tubing by a cable tie, but it doesn’t seem to have any insulator, and anyway it plugs into the board). The other plugs connect the fan and, I think, the heater.
The pictures of the part don’t show the “large insulator”, so I don’t know what it looks like. I don’t know if it means a thermal insulator or an electrical insulator. It could be what the white cylinder is, but then the air sensor isn’t supposed to have the large insulator. They both seem to have heat-shrink electrical insulators to put on the bare twisted wires. I think I’m fine about fitting the wires – I just don’t know what to do with the business end of it, and if it’s the right part.
I’ve been trying to sort this out for about 3 weeks, while the freezer is plugged into a mains timer – actually works pretty well on 50-50!
It went back to working properly for a while after I took it apart, waggled things, and put it back together, but it’s since dived down to -26 C with no sign of switching off (ignoring the temperature setting in the fridge). If you have other ideas about what’s wrong, don’t hesitate to share them, please. I don’t mind replacing a few parts at under a tenner each instead of calling an engineer in. It wasn’t badly frozen up. Hardly any ice melted out when I defrosted it. The drain is clear. The fan is working properly, apart from never stopping! I took it apart again and put a bit of light oil on the contacts of all the plugs, but it’s still apparently trying for absolute zero.
Just to add to the confusion, I contacted Beko and they said that my model doesn’t have an air sensor. They didn’t seem likely to go into any more detail, and the engineer said they don’t know what they’re talking about, but I suppose I could quiz them further if I can’t get any more clarity.
The f/f serial number is 1110854905.
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
Beko are correct it does not have an air sensor on this model.
The sensor in the freezer is the defrost sensor.
The sensor and thermal cut out in the freezer only controls the auto defrost and not the temperature.
The temperature is controlled by the potentiometer and control module.
If you have ice on the bottom of the fridge is the drain hole at the back inside the fridge blocked.
If the back of the fridge gets cold and frost evenly on the wet wall at the back then
It is the control potentiometer and control module/PCB that you need to replace both cheap on this model.Bob
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
Thanks for your reply, Bob. I don’t think the drain tube is blocked – I cleaned the fridge inside and out just before it went wrong and checked water ran down it. The back of the fridge is frosted and when it went wrong the ice was covering the gaps down the back of the shelves.
I’m gobsmacked – if “Fred Bloggs” at justanswers.com has been giving me the wrong advice all this time I’ll be livid – I paid for that – and he must have sent me that pdf that doesn’t even apply to my FF. The latest was I asked him why it doesn’t look the same as the part that’s in, and how I fit it, and he said he didn’t have anymore information and closed the conversation.
But I’m puzzled now about your advice: I can understand that the potentiometer and control module controls the temperature, but surely the FF must have sensors to detect what the temperature is? Sorry to sound sceptical, but I’ve had so much contradictory advice and I’m just trying to figure out who’s got it right. Are you confident – do you know this model well?
If so, I’ll be well chuffed – I think my local electrical store has the pcb assembly and it’s a couple of minutes to fit it. I was going to give it a go before I started researching this ages ago!
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
I have repaired a few with the same problem.
In most case’s the control model fails and the appliance stops working.
I have had about three with the. Fridge frosting up and have replaced the
Potentiometer & Module and it has solved the problem.So without being able to test the fridge / freezer I am pretty sure this will cure the problem.
The PCB and control are not expensive and easy to replace so it is worth giving it a go
Bob
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
Nope, that didn’t work. Not sure what to do next – maybe time to call in an engineer to look at it, or keep replacing parts until it’s fixed!
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
Hi,
I have a problem with the same fridge freezer. In my case the top fridge has a problem regulating temperature and freezes everything inside. I guess the most obvious answer is to change the Potentiometer/thermostat. Any advice on where to get a replacement?
Cheers,
Santi
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
Just an update to my previous post.
I have replaced the Potentiometer/thermostat in the fridge compartment (inside the box where the fridge light bulb is) and checked the thermistor in the freezer compartment (20-30cm white cable with a plastic black cylindrical box at the end). However the fridge is still freezing solid anything in the fridge compartment. The fan in the freezer is also continuously working.
In the meantime I am managing following John’s advice of running the fridge on and off 50/50 using an old ikea electric timer I found around the flat.
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
Just an update on this, as I’ve had a few private messages asking if I’ve fixed it…the bad news is no, I’ve given up. Changing the PCB/potentiometer module in the light housing didn’t work. The good news is that plugging the fridge into a mains timer solved the problem well enough to get by for the last six months, and I see no reason not to continue with it like that. It’s one of those mechanical rotary timers with switches you push in or out for each 1/4 hour of the clock. Some cheaper ones just have half-hour sections, which might work, but might be a bit coarse for this. And it wouldn’t work with one of the other type that just allow a few on and off times (digital ones usually do that).
I was concerned that doing this might interfere with the defrost cycle, but it’s still frost free (I have another freezer that isn’t auto-defrost, which I have defrosted in that time, and it needs doing again now). I was also a bit concerned because freezer instructions usually say to leave the unit off for a long period if you have to switch it off for maintenance purposes or something, but perhaps it’s not switched off long enough to need it. Anyway, the only observable difference from how it used to function is that the light won’t come on in the fridge when it’s in its off cycle, obviously.
If you’re thinking of doing this, I’d recommend keeping a suitable thermometer in the fridge, and adjusting the switches on the timer accordingly, which requires a bit of basic maths and common sense. My 50/50 setting (switches like this: 101010…) was too cold, so I tried 1/4 hour on, 1/2 hour off (100100100100…), but that was too warm so it’s now alternating between the two (1010010100…). It doesn’t have to match perfectly. I find it’s a bit warm, I can just flip a few of the 0s to 1s fairly evenly round the clock, or vice versa. Half an hour on or off is no problem with the insulation it’s got. More than that might be a problem.
Fridge and freezer temperatures are fairly important to avoid food poisoning, so make sure you know what you’re doing or get help. It may also need adjusting at different times of year in temperate zones if you don’t keep the room temperature constant. I’ll be checking mine again soon here in the UK. I even wondered about making it work harder during the day and less at night, but it’s probably not necessary.
I’m pretty sure if you get the fridge the right temperature, the freezer should be ok. This model only has a single adjustment, although it normally monitors the freezer temperature. If in doubt, get a good low-range thermometer and check the freezer too.
Several people with this never-switching-off issue on this model have replaced the “thermostat” in the top of the fridge to no avail, so if you’ve just had it happen, you could possibly save yourself a tenner for it and spend that on a mains timer instead. (Sorry I didn’t get your post in time Santi). However, Bob (Samuri) says he’s fixed several of these by replacing that part, so I’m no clearer than I started. I have even wondered whether we should have left the freezer for 48 hours or reset something (or done a little raindance maybe) after changing it, or whether half of them come off the production line not working!
The other option might be to replace the sensor (also cheap, but not a simple plug-and-play affair, you have to wire it together and then heat-shrink the insulation on), but I’m still not sure which of the little gizmos it is (there are two that look similar), and I can’t be bothered taking it all apart again, letting it warm up to work on it while storing the contents in another freezer and doing the wiring job. Santi, I don’t understand – when you say you’ve “checked” the thermistor – how did you do that? Isn’t it hard-wired into the machine, and even if it’s plugged in, how do you check it’s working?
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
In case anyone wants to try the PCB, this is where I got mine for under £8 including postage. http://www.buyspares.co.uk/beko/ca7015f … ref=648148
But now I’m even more confused. I just searched on ukwhitegoods, and they have the “control module” for this f/f here http://shop.ukwhitegoods.co.uk/43606201 … rol-module for £19.48, and as well as being much more expensive, it looks completely different. It doesn’t fit in the top of the fridge, and doesn’t appear to have a potentiometer. It looks bigger. Where…? What the…!?
Won’t buy a Beko again (unless it’s cheap lol).
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
Hi John,
Thanks for your post. Just to recap on my experience trying to fix this fridge.
– I replaced the control unit at the top and that didn’t work. I got mine in Amazon for about £5
http://www.amazon.co.uk/gp/product/B009 … UTF8&psc=1
– I have also tried switching it off completely and leave it for 24 and 48 hours just in case it was down to ice build up somewhere. It didn’t work either.
– The thermistor I tested (I think that’s what is called) is the long white cable with a black plastic small cylinder box at one end. I’ve pointed it out in the picture submitted above. Following some youtube videos I unplugged it from the fridge and tested the Ohm resistance and Continuity with a multimeter. The readings for resistance were about 0.02 (200 ohm setting on the multimeter) at room temperature and dipped in a glass of ice water. I was expecting a change in behaviour at low temperatures but perhaps the ice water wasn’t cold enough. My guess is that this thermistor is there to trigger the defrost cycle and it’s not linked to the fridge temperature but I could be totally wrong. :rolls:
– I noticed the other ‘sensor’ (single black cable in the picture ending in a white plastic cylindrical box) but as John says it’s hard-wired so I thought I should leave that one alone.
After all this I’ve given up and gone the mains timer route which seems to work perfectly well, thanks again John. I’ve set up mine back to 1 hour on / 1 off and placed a min max thermometer inside to keep an eye that the temperature doesn’t drop to much when it’s off.
And yep I agree that the fridge control module suggested in ukwhitegoods doesn’t look at all like the one in the actual fridge. I didn’t buy this fridge but I will certainly think twice before going for any other Beko products.
I hope this helps
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
I have an identical problem on a Beko CF6914 (which appears identical from the photos), where the freezer fails to regulate and the temperature gets far too cold.
I think you are confusing the auxiliary pcb in the top of fridge compartment with the main control pcb sited in a compartment on the rear top of the appliance. The former just comprises a potentiometer which feeds a small change in resistance to the main pcb when the temperature dial is adjusted. As stated there is no air temperature sensor as such, although strangely the replacement part is often called this. On my unit I have replaced both the sensors and the main pcb, and have checked out the auxiliary pcb, yet still the fault persists. I have checked the wiring wrt to the main sensor (the top one) and the aux pcb to the main pcb and all is good. The sensors check out fine too. So what is wrong on these Beko appliances? I am tempted to suggest a wiring fault somewhere in the foam – but how and why – it seems unlikely? Or is the replacement pcb faulty perhaps? I do not have a wiring diagram and am puzzled as to the source/destination of the orange/grey pair connected to socket KN3 on the main pcb, Would have expected these to connect to the lower sensor (temperature switch) but they do not – so where do they go, and where does the sensor switch route to if not the main pcb? Is there a further controller somewhere perhaps? Am tempted now to hack away the foam on the rear to get to the wiring but can anyone put me out of my misery first please? Am I missing something? Thanks.Re: Beko CDA543FW-2 fridge freezer air sensor replacement
I’ve tried to stay quiet on this thread but, here’s the deal… apologies in advance for the bluntness…
Putting a fridge or fridge freezer on a timer is nuts, barmy and potentially dangerous.
The temperature will not be correct, it will not cool properly and could lead to bacteria growth in your food.
So if you do this then die from salmonella or something, don’t say you weren’t warned. Not that you will be able to if you die of course or, if your children get sick or worse.
The temp in the freezer is regulated but the temp in the fridge so, if the fridge is wrong.. guess what? That’s right, all the frozen food will not be getting stored correctly and, bacteria growth in the food.
Sell or use by dates will be even less use than they already are.
Sorry but it’s so dangerous people need to be aware that this is a VERY bad idea!
There is a small potentiometer board in the light housing, other than telling the main control unit what temperature you want, it does nothing.
The other board is the one that actually has some “brains”.
But, it only does what the thermistors tell it to do by way or reporting back to the board, which in turn switches the compressor on and off, runs the defrost cycle and so on. That means, back to a time, if you put it on one it is not operating or defrosting properly.
And, what happens if it gets stuck on defrost and burns your house down, it won’t seem such a smart idea then will it?
There are multiple article on thermistors, how they work and some on these Beko ones on the site, we give you that for free, thanks for advertising other retailers that don’t even give you that let alone the help on here but I digress. You need to read about them before you start tinkering, understand what they do and why, all the info for these you need is as follows:
http://www.ukwhitegoods.co.uk/help/fix- … hermistors
https://help.ukwhitegoods.co.uk/support … er-sensors
http://www.ukwhitegoods.co.uk/help/fix- … hermistors
All the info is there to allow you to repair these and replace the thermistor. There is no short cut, there’s no hack to get around it. The thermistor will need to be replaced in 99.99999{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} of cases or, you will not solve the problem.
K.
Re: Beko CDA543FW-2 fridge freezer air sensor replacement
Hi kwatt,
No need to apologise, and thanks for the information. It might have been good not to lurk but jump right in. I appreciate your concerns and you’ve prompted me to think it’s time to get this professionally sorted. I haven’t got the time to dig about in the thing again and research which parts might need to be ordered. This is why I ended up taking a cheap and dirty solution of the timer – my research gave me contradictory information, photos that didn’t match the item, etc., etc., and I didn’t feel I could afford the hundreds of quid it might cost for callouts and parts and labour, or a new fridge.
I went into it with my eyes open and have had a max-min thermometer inside the fridge since, which I also check in the freezer now and then. I also keep an eye on it when the weather changes to adjust the on-off times.
I’m probably in less danger than most since we’re vegetarian, so there’s less risk of salmonella poisoning, but sure, folks who just bang a timer on a fridge-freezer, don’t check the temperature and store loads of meat and poultry in it are in serious danger.
I don’t think it ever goes into defrost mode, and I don’t imagine there’s much risk of it getting “stuck” in defrost mode, especially if the timer cuts it off. Not compared with any other fault developing that could cause a fire. However, if my heath-robinson affair causes a fire, the insurance might turn out to be null and void.
So yeah, on the whole, good points, well made. I’ll call the guy that hacked into my washing machine when it wouldn’t open!
Cheers
J.Re: Beko CDA543FW-2 fridge freezer air sensor replacement
I am now able to give a solution to the problem with my Beko CF6914. The fault found is almost certainly that which numerous other owners of this model (and similar ones including the one entitling this thread) have been trying to find. Firstly let me say that there is a lot of poor, misleading and just plain wrong advise out there which leads you in the wrong direction, so beware, and perhaps beware of what I am saying also!
I asked earlier where KN3 cabling was routed – well the answer is, I believe, to a fridge sensor buried somewhere within the foam insulation on the rear of the fridge. The clue was that the KN3 cabling presented an impedance of about 11k at ambient, rising (but fluctuating indicating a fault) with decreasing temperature, suggesting termination with an NTC thermistor. Some further searching on line revealed that burying sensors within the potted insulation is standard practise with Beko and certain other manufacturers – great!
My method was to dig away some insulation behind the fridge, quite near to the main pcb and install a new sensor (I think Beko use the same one as in the freezer) in the space formed. I used thermally conductive adhesive (and a piece of carefully shaped tin wrapped around the sensor to improve thermal contact) to glue the sensor to the rear surface metal of the fridge. The sensor cable was carefully routed through the potting and through a small hole I drilled in the plastic pcb holder then connected to KN3. Expanding foam was used to make good the missing insulation and further secure the sensor. I am pleased to say that the appliance now runs with the fridge and freezer on around 4 and -18 degrees C respectively, so success I think.
Tbh it is hard to see exactly what the fridge sensor actually does given that there is no independent regulation of the fridge temperature – as I understand it the fridge is cooled due to its thermal mass being in close proximity to that of the freezer and an equilibrium or temperature gradient results. There is no air ducting. I would guess that the controller looks at both sensors (freezer and fridge) and tries to alleviate over temperature should a door on either be left open. This would of course force one or the other to go under temperature but this presumably is preferable from a food safety consideration. Interestingly the appliance appears to work ok with the fridge sensor removed altogether (pull out the plug on KN3). This means that probably the controller is programmed to completely ignore the sensor input when the impedance read on KN3 is infinity. Thus no sensor is better than a faulty sensor!
Finally, there seems to be quite a few folk pulling there hair out over this over cooling issue so maybe Whitegoods might like to say why both they and other professional appliance forum moderators usually never mention the existence of the fridge sensor – presumably they do know about it!?
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