Replacement transformer for Samsung fridge

[unimatrix93]

Dear forum

My Samsung fridge died from a fault on the mainline and the transformer (https://www.hqelektronika.hu/hu/halo...-w8-da2600009k) died.
No voltage on the secondary, measuring resistance shows open circuit. I concluded a blown fuse which is deep inside the transformer, I don't think I can disassemble it to replace the fuse.

The second problem is that I cannot find an original replacement part anywhere or even If I do it's pretty expensive.

My question is: Can I replace this transformer with a generic 230V to 17V one? The output has 4 wire and most that I can found on local suppliers like TME has only 2 like this one: https://www.tme.eu/hu/details/tszzba...szzba-65-002m/

Thanks in advance!

[CapLeaker]

Huh? The heat fuse is in the primary, not in the secondary side of the transformer. I highly doubt the secondary is open. Check that transformer again.
Doesn’t matter what you put in order to replace it as long as you get the voltage you need to all the voltage rails. Probably the low voltage AC gets rectified into DC on the board the secondary of the transformer plugs into. Let’s see… 16.5VAC x 1.414= 23.3VDC. I suppose you could take the rectifier diode out and place a 24VDC switching power supply. Possibilities to do a hack, no problem. You just got to understand the circuit.

[Agent24]

If it has 4 wires it probably outputs two different voltages.
If you analyse the circuitry it connects to, you can probably guess what the other voltage is supposed to be.
Then you could probably replace it with two different transformers supplying each the different voltage.

[unimatrix93]

After some digging I found the diagram of the fridge:


It looks like it produces 16.5V and 13.5V on the two secondary.

[CapLeaker]

So one rail makes ~24VDC and the other around 19VDC. I guess there must be some rectifiers on the main board. However, it may be easier to fix the thermal fuse in the transformers primary, unless you got a PSU that outputs 24V and 19VDC simultaneously.

[Agent24]

You have to be sure there's nothing using the 60Hz AC signal from the transformer as a time/clock reference or something too, if you decided to use a DC power supply instead.

If you can't fix the transformer, two separate ones should work too.

Also have to wonder if some fault on the main board overloaded and killed the original transformer.

[unimatrix93]

You have to be sure there's nothing using the 60Hz AC signal from the transformer as a time/clock reference or something too, if you decided to use a DC power supply instead.

If you can't fix the transformer, two separate ones should work too.

Also have to wonder if some fault on the main board overloaded and killed the original transformer.

I see, thank you for your input.

Can I use these two transformers?

https://www.tme.eu/hu/details/ts10_3...ndel/ts-10-30/
https://www.tme.eu/hu/details/tszzba...szzba-19-001m/

[unimatrix93]

So one rail makes ~24VDC and the other around 19VDC. I guess there must be some rectifiers on the main board. However, it may be easier to fix the thermal fuse in the transformers primary, unless you got a PSU that outputs 24V and 19VDC simultaneously.

Well you are right about the thermal fuse, but the problem is that it seems its buried deep inside the transformer, I don't think I can disassemble it to get to it.

[CapLeaker]

Well you are right about the thermal fuse, but the problem is that it seems its buried deep inside the transformer, I don't think I can disassemble it to get to it.

Just give it a try. It’s broken anyways…

[unimatrix93]

So one rail makes ~24VDC and the other around 19VDC. I guess there must be some rectifiers on the main board. However, it may be easier to fix the thermal fuse in the transformers primary, unless you got a PSU that outputs 24V and 19VDC simultaneously.

So after some search I ordered two transformers that outputs the almost same voltage. Couldn't find anything closer to it.

I took off the connectors of the original transformer and I want to build it like this.
Is this correct?


(Please ignore the missing insulations and such, I will finish it up once it's aproved to be okay. )

[CapLeaker]

There is a lot of cleaning up to do. You wouldn’t want something to short out later. While this arrangement does work, now I wonder what happens, if one transformer dies and the other keeps going. Before you would loose both low voltage AC supplies…
Hope there is room to fit all that…

[unimatrix93]

There is a lot of cleaning up to do. You wouldn’t want something to short out later. While this arrangement does work, now I wonder what happens, if one transformer dies and the other keeps going. Before you would loose both low voltage AC supplies…
Hope there is room to fit all that…

Sure, I will do all the cleanup before the live setup using shrinkage tubes and insulation tape. There should be enough space since the main board is on the top of the fridge.

[unimatrix93]

There is a lot of cleaning up to do. You wouldn’t want something to short out later. While this arrangement does work, now I wonder what happens, if one transformer dies and the other keeps going. Before you would loose both low voltage AC supplies…
Hope there is room to fit all that…

What is interesting that the supposedly 17VAC transfomer has 23.5V on the secondary. And the 14V has 18V. The 14V has 3 pin on the secondary winding and the second pin has 15V.
Is this normal?

[lotas]

These overvoltages without load...

[CapLeaker]

Yep, you got no load on it, Put a load whatever the transformer is rated for and the voltage drops to the desired voltage.

Means: if you oversized the transformer, equals higher output voltage.

[unimatrix93]

Yep, you got no load on it, Put a load whatever the transformer is rated for and the voltage drops to the desired voltage.

Means: if you oversized the transformer, equals higher output voltage.

Thank you for the explanation. Since than I installed the transformers and the fridge is working. Yay!

The only problem is that it's never stops cooling...What could be the cause? Bad thermostat?

[CapLeaker]

What you mean? The compressor never turns off and it’s building ice in the fridge?

[flat-earther]

My fridge once developed a problem where the compressor never turned off and the evaporator was just building ice indefinitely.
I found the culprit was a wire that connected to the compressor's terminal was broken off and after reconnecting the wire the problem was solved.
I don't understand how the broken wire caused the problem but that's what happened.

[Agent24]

The fridge will take a longer time than usual to cool down from being unused for a while, but if the compressor is really running constantly, then maybe something on the control board was damaged when the original transformer failed?

I don't know how the compressor is controlled by the logic board - relay or something else? But maybe whatever switches it on and off (and/or whatever drives that) is shorted?
Even relays can fail short if the contacts weld together.

[stj]

or a sensor wire got unplugged by accident?