Weller EC 2002 soldering station repair.

[NA5B]

My Weller EC 2002 stopped heating and the display was erratic, numbers jumping all over the place. I replaced all the SMD capacitors with regular ones. Now it is working again. :-)
My experience with these SMD capacitors is that they are basically no good. These were used in the past for a time in millions of electronic products. Many of these products such as computers, radios, camcorders, and computer systems have been trashed by the premature leakage of these caps.

[abdulbadii]

Would you share please how exactly did you do all the accomplishment in detail steps?

[NA5B]

I checked the soldering gun heater resistance and the thermal sensor and it showed normal. The transformer checked ok. Tested the regulator IC and that also showed ok. I removed one of the electrolytic capacitors without physically damaging it in order to do measurements. The cap showed bad. I figured they are all bad and replaced them with regular ones. The PCB is ceramic so I had to use a 70 watt soldering gun to replace the parts.

[Haenk]

Almost 30 years of use, not too bad, after all.
My bet: That odd KNT cap will not survive 30 years

Edit: There are branded long life SMD replacements available - that would have been my choice for this not-that-cheap station.

[tooki]

My experience with these SMD capacitors is that they are basically no good. These were used in the past for a time in millions of electronic products. Many of these products such as computers, radios, camcorders, and computer systems have been trashed by the premature leakage of these caps.

Uhhhh… it failed after 29 years. You call that “premature”? That’s “no good” to you?!? That’s absolutely unreasonable. Get a grip!

Installing replacement through-hole caps has zero advantage over installing new SMD caps: the electrolytic capacitor plague of the early 2000s affected SMD and THT caps alike. But the THT caps pressed into SMD service are unsupported and will put extra mechanical stresses on the traces.

[NA5B]

My experience with these SMD capacitors is that they are basically no good. These were used in the past for a time in millions of electronic products. Many of these products such as computers, radios, camcorders, and computer systems have been trashed by the premature leakage of these caps.

Uhhhh… it failed after 29 years. You call that “premature”? That’s “no good” to you?!? That’s absolutely unreasonable. Get a grip!

You know what, I agree with you. 29 years plus heated environment being near the transformer, those caps lasted for a long time in my case. (What I tried to mean by premature leakage, is that some low-quality electrolytic caps not only go bad in 5 years or so, they also leak on PCB and destroy the PCB traces)

[tooki]

You said “these caps” in your opening post. But these ones didn’t fail prematurely. So you’ve inexplicably commingled a story of repairing a device after a long service life with another story of general whining about low capacitor quality, even though the electronics world knows how and when the capacitor plague occurred, and knows that it wasn’t a problem before or after that specific window (1999-2007), nor did it affect the big name brand cap manufacturers.

The original caps in your station preceded the capacitor plague by many years. They’re not victims of it, they simply died of old age.

And even if they’d been from the correct time frame, it’s unlikely that Weller would have used one of the affected Taiwanese brands.