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enter image description here

My washing machine has just stopped working - no signs of life, and a slight burning smell.

Can anyone tell me from the attached image whether this board is likely the cause of the issue?

I suspect the brown / bulging capacitors are no good, but I'm unsure.

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    \$\begingroup\$ If you have no experience handling mains voltage electronics then please be very careful with this. The various caps can hold charge for a good while after you disconnect the power. They will need to be safely discharged before you do anything else. As a hobbyist you should use special tools suitable for this and don't attempt anything crazy like discharging through a screwdriver etc which might damage the board further. \$\endgroup\$
    – Lundin
    Sep 12, 2023 at 8:34
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    \$\begingroup\$ The caps are bad, but most likely only the symptom not the cause, since 2 possibly 3 are bad. Other parts may be damaged. Odds are you will spend a lot of effort and it still will not work. \$\endgroup\$ Sep 12, 2023 at 11:34
  • \$\begingroup\$ Google the model number and what people also bought. If it was a dryer it'd be an idler pulley. Washers... the gear box? (that's no fun). Or 'these are crap; board burnt out in 3y'. (means buy something else). - Can a bad capacitor on the motor cause wear on the board? \$\endgroup\$
    – Mazura
    Sep 14, 2023 at 3:06

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Yes, those two caps (top left and the brown-ish one in the middle) are definitely defective. These types of electrolytic capacitors tend to fail in this way (crack open) after years of use.

If you're lucky that is the only fault though, so replacing the capacitors might be all that is needed to repair your washing machine. Be careful though, you need caps with the same rating and orientation, electrolytic capacitors are polarized and will fail when inserted the wrong way!

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  • \$\begingroup\$ I first though "huh, that's a strangely transparent/oily electrolytic leak", but then realized it's conformally coated; that's nice, because damage going to be very localized, but it's annoying, because this makes replacing caps harder \$\endgroup\$ Sep 12, 2023 at 6:43
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    \$\begingroup\$ The orientation is which side has the white (-) (-) (-) marking. \$\endgroup\$ Sep 12, 2023 at 8:53
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As others have said, those two cracked capacitors are bad and you should replace them with the same or higher voltage and capacitance rated caps.
For example, the 470uF/35V can be replaced with 470uF to 1000uF capacitor rated for 35V to 63V, as long as they physically fit on the board and don't press on the components around them.
The high voltage capacitor is not readable, but if it's rated 10uF/400V for example, you could use 10-22uF, 400V to 450V.
The 470uF/35V one has to be replaced with a LOW ESR capacitor, typically rated for higher temperature as well, like 105°C. Definitely do not replace it with a capacitor marked with 85°C!

You should also check the chip/IC (integrated circuit) which is marked as LNK306PN to see if it has ANY cracking/chipping on it, meaning it is blown/destroyed. There is a 90% chance it is bad.

Its input (mains) fuse could be burned out as well.
I would also check the smaller capacitor next to the IC, the one covered with the white glue, just to make sure it is good.

Finally, I suspect the designing engineer didn't provide enough cooling surface for the IC or he didn't count on the glaze being used for moisture protection, which would reduce the cooling and increase the temperature of the IC during operation.
The board and the capacitor around the IC being darkened are obvious signs of overheating, while the IC manufacturer recommends no more than 100°C temperature on the IC's pins. Its manual is located here: https://docs.rs-online.com/3734/0900766b815f08d8.pdf
On page 5, it lists the thermal recommendations:

enter image description here

Personally, I would either add a thick silicon pad below the IC to transfer its heat to the metal below it or I would add a small heatsink above it to keep it running cooler.

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Yes, it's bad, due to bulging caps with electrolyte leaking out.

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