Soldering iron out of control?

[moosapotamus]

Anyone ever have their soldering iron start overheating uncontrollably for no apparent reason?

I'm using a Xytronics with a digital temperature control (137ESD). With the temperature set to minimum, the readout goes up to ~330 degF, but the tip gets glowing red hot. I replaced the tip, and that seemed to solve the problem for about one day. Now it still just keeps overheating like crazy. It's unuseable.

I can call or write to the company or Circuit Specialists (where I bought it), but I'm thinking "the man" is just going to tell me to send it in to be "checked out". I don't really want to do that.

So, I was just wondering if anyone here might have had a similar problem and/or possibly know how to fix it.

Thanks!
~ Charlie

[Herr Masel]

No, sorry, but my temp controlled iron gets emotional if the temperature is above ~250c. I tin it and withing a few minutes I have to clean it because the solder turns to gunk..

[petemoore]

  Have a spare to use while the other is being 'looked at'?..

[moosapotamus]

Yeah, I had to blow the dust off of my old rat shack iron last night. Damn, that Xytronics is soooo nice... when it's working.

Thanks
~ Charlie

[Peter Snowberg]

What a bummer.

It sounds like the triac that controls the heater is frozen on.

What does the heater light do at turn-on and throuogh the overheat process? There may be a simple Radio-Shack fix.

[soundcollage]

Make sure you post the fix if you find one. I have the same Iron, no problems yet in two + years, but who knows.

[gaussmarkov]

argh. that's frustrating.

i just got a xytronics 379UL from circuitspecialists based on the advice in this forum.  i would like to leave the feedback for other newbies that these temperature controlled irons are the way to go.  if it were up to me, i'd put this advice in the FAQ.

i have been using a simpler iron (i don't remember the brand) that was running too hot, but i didn't know that.  well, i suspected it was too hot because of things that other people have said.  when you get the right temperature, everything is so much easier and works the way people describe good soldering.  the solder really does flow onto the tip when you tin it and it stays silvery.  i managed to get a bunch of projects completed with the old iron, but it was a lot harder than it needed to be.

i think i will install a simple rheostat for my old iron.  i should be able to get the right setting now that i have actually seen how it is supposed to work.

charlie, apologies for this short hijack.  especially one that celebrates a working iron.     at least i can appreciate why you are unhappy. 

[moosapotamus]

What a bummer.

It sounds like the triac that controls the heater is frozen on.

What does the heater light do at turn-on and throuogh the overheat process? There may be a simple Radio-Shack fix.

Yeah, I'm like a dog without a bone... a mustard without a ham... like a... like a... uh, yeah... it is a bummer.

The heater light just stays on the whole time, never goes out.

I guess I should at least peek inside the box. Would be great if it's something simple.

Thanks
~ Charlie

[Johan]

you probably have some sort of temperature indicating resistor, most likely a PTC inside the tip-holder, driving a comparator in the station and having the temperature-pot seting the threshold...could be as simple as a bad connection..

johan

[rockgardenlove]

I use my 15$ Radio-Shack iron...its simple, but it works

[moosapotamus]

you probably have some sort of temperature indicating resistor, most likely a PTC inside the tip-holder, driving a comparator in the station and having the temperature-pot seting the threshold...could be as simple as a bad connection..

johan

Thanks, Johan. I've had the tip holder apart several times, changing tips. But, I'll tinker with it some more.

I use my 15$ Radio-Shack iron...its simple, but it works

Yeah, my rat shack iron works, too. No disrespect, but... A 1963 hatch-back with one brown door will get you to work in the morning, too. And, if you've never used a decent soldering iron, you probably wouldn't know any better.

Thanks
~ Charlie

[Paul Perry (Frostwave)]

The difference between cars & irons, is most people can afford to keep a cheap iron as a spare. (I've got no car, but I've got 3 irons..)

[Peter Snowberg]

The difference between cars & irons, is most people can afford to keep a cheap iron as a spare. (I've got no car, but I've got 3 irons..)

LOL, I'm in the exact same boat.

I got no car and it's breaking my heart,
but I've got 3 irons and that's a start! 

[moosapotamus]

Well, I've got two irons and one car... I'm glad my car is not overheating.

~ Charlie

[gez]

Hmmm, something to all this...

Regards

Gez "3 irons and no car" Paton

[HWV]

Hi there! First post with something I can actually contribute!

I have a 137esd; ran into a similar problem: one of the wires had broken off of the tiny circuit board inside the handle. I fixed it by loosening and removing the black knurled plastic thingy at the (hot) end of the soldering handle. Then push the cable and heater element assy. through the handle to view/ repair (it isn't attached to the strain relief). Simple as that!

Hopefully that is the problem - I believe the wire on mine broke because the strain relief wasn't doing it's job. It was pre-bent from the box it came in. 

-Hans

[gaussmarkov]

Hi there! First post with something I can actually contribute!

how cool is that? 

[moosapotamus]

Right on, Hans! I'll be checking that out tonight.

Thanks!
~ Charlie

[Peter Snowberg]

Very cool! Welcome to the forum HWV!

Charlie, I was going to suggest checking continuity of the temparature sensor with a meter. I'll wait for news on this solving the problem. 

[HWV]

Very cool! Welcome to the forum HWV!

Thanks for the welcome, guys!

I hope all goes well with the soldering station.
-Hans