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JamesI, Handyman
Category: Appliance
Satisfied Customers: 2155
Experience:  I have repaired and maintained numerous items over the years, from fridges to freezers, radios to TV's.
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Samsung american fridgefreezer not cooling

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samsung american fridgefreezer not cooling

This sounds like a circulation fault where ice is blocking the coolant duct, a defrost would probable fix it but since you only defrosted it a few weeks ago I think it worth getting an engineer to site to strip it down and find out whats causing the build up of frost.

Before booking an engineer please check the doors seals are in good working order and the door is closing properly, if the door is closing and seals are not damaged, it may be the defrost sensor is not working so the frost is building up and blocking the coolant duct.

If you provide your postcode I can suggest a suitable engineer to attend.



This may be due to a faulty defrost sensor,

Customer: replied 1 year ago.

hi there. i do have some knowledge with this but need some help. this machine is running warm in the fridge and freezer area. i will be looking at this tonight. if there is no ice build up what could it be apart from the defrost sensor or seals, as it is running warm.

If we rule out the problem being frost stopping the coolant leaving the elements and circulating around the appliance, and note that both fridge and freezer are running warm, I would tend to think its may be the termostat, control board or compressor.

Thermostat fault - there are two one in the fridge and one in the freezer, but as fridge gets its coolant from the freezer, if the freezer is running warm it restricts how cold the fridge can get. So I would check the resistance on the thermostat for the freezer, best accessed b removing the control panel.

Compressor fault - Check if the compressor is warm \ hot to touch, if it is it suggests it is working, if this failed it would be uneconomical to repair, its unlikey the fridge has lost its coolant gas, but again if it has, I would suggest it uneconomical to repair.

Control board - if the thermostat resistance changes as you apply ice or warm water to it, but the fridge isnt calling for coolant then the fault is most likely due to the control board. Control boards cost around £100, make sure you buy a pre-programmed one.

Appreciate if you can rate the service received, if after this evening you cant find the fault, send me your postcode and I will happily recommend someone to come out.

Customer: replied 1 year ago.

hi there, i managed to check this machine today and the ice is actually built up half way at the back of the fridge and freezer sections. the fan is working next to the comp and the comp seems to be working ok. there is a cylinder above the comp and a tar like stuff has dripped down over the comp?????. there is no fan action in the fridge or freezer areas as i assume it is jammed. the display still shows fridge and freezer at 15 and 17oc. the comp does not seem to be faulty.

I suggest you start by doing a 24 hours defrost, to clear the size away from the fridge and freezer back panels.

This is most likely to fix the fault, as the ice is probably blocking the cooling duct.


I haven't heard from you in the last few days, please let me know if you need any further assistance, if not I would appreciate if you could rate the service received.

Many thanks

Customer: replied 1 year ago.

hi there. been busy. this machine was defrosted before and lasted 3 weeks before it iced over again. i have defrosted it again. what do you think.

The fact its frosting up within a few weeks, I think its likely to be a faulty thermostat, if you have already checked the door seals are in good order.

If the thermostat is creating a temp delta eg cooling to -20 then letting it warm to -10 before cooling again this will cause a build up of moisture and create frost.



Customer: replied 1 year ago.

hi there, thanks for your time. when i search for a thermostat i get temp sensors coming up. can you let me know the part i need. 2 fridge and freezer and 1 defrost sensor, thanks.

Sorry for the delay, its the same sensor for fridge, freezer and defrost.

The part is no longer being distributed to third parties, however I did manage to find it on amazon here.

Samsung' distributor (4mysamsung) are able to provide the sensor including delivery for £27.

You just need to call them on*********** select option 5, quote your model number RS21DCNC and request a temp sensor.

Please let me know if you need anything clarified, otherwise I would appreciate it if you can rate the service received today.

Many thanks


I haven't heard from you, please let me know if you need any further assistance, if not I would appreciate if you could rate the service received.

Many thanks
Customer: replied 1 year ago.

hi there, this macine has run for 3 days and ice has started to build up in the lower part of the fridge. there is a noise like a fan hitting off ice. can you tell where the sensor is that i need to change. many thanks

The sensors will be located in the rear back compartment, you need to remove the rear fascia, which should expose the fan

Customer: replied 1 year ago.

hi there. sorry is this in the fridge or freezer area

Sorry this will be in the fridge there should be great where the fan sits behind, about 2/3 up on the back

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Customer: replied 1 year ago.

hi there, i replaced the sensor in the fridge and it is still freezing over and the fan is rubbing. can you please help further

Sorry to hear this didnt resolve the issue David.

To better assist you can you help me out with the following:

When did you last defrost the fridge?

What is the fan rubbing against, the case, the frost?

Is both fridge and freezer still running warm?

From what you have said to date, this is most likely a faulty PCB as if the sensors are working properly and the fridge isnt reading the input correctly it will be the PCB, unfortunately this is a rather costly part (upwards of £100). The benefit is if you know its a costly part paying for a repair a protect plan eg for £200 means your getting value for money and also ensuring the fridge is under a further years warranty.

I will await to hear back and suggest how we go forward from there.