Older Weller soldering iron won't heat?

Question

I inherited a Weller WTCPL soldering station a while ago:

It was my grandpa's, and although I can't find a direct reference to it anywhere on the net, I'm guessing it's anywhere from 40 to 60 years old. It worked for some time, but sadly, it recently has stopped. When I was soldering the other day, I noticed the wand getting progressively colder, until it eventually wouldn't even melt solder. Now, it turns on (or at least the indicator light does), but the iron does not heat up. Is this fixable or do I need a new iron?

Answer 1

The WTCPL uses the same soldering pencil as the WTCPT, which I inherited some time ago, and Weller (now part of Cooper) still makes new replacement parts and tips for these old workhorses, which I think is fantastic.

Anyway, you'll find the datasheet for your model here, including troubleshooting guide, assembly diagram and parts list:

Weller Tech Sheet - WTCPL Series

In my case the magnetic switch was still working (there's instructions on how to test each part) but the heater barrel was open. I replaced the barrel and the nut (the newer barrels are slightly larger in diameter, so you might as well get a barrel nut at the same time) and the iron works perfectly.

You can get these parts from Digikey:

EC234-ND - HEATER ASSY FOR A TC201T IRON
BA60-ND - ASSY BARREL NUT FOR PES51&50
SW60-ND - SWITCH ASSM FOR SOLD PENCIL (magnetic heater switch)

Some are listed as zero quantity, but they order them and I got mine in about 2 weeks. Other replacement parts are available, but if you have to replace too much (or the more expensive parts) on the iron you might as well buy a new iron. When mine broke, I fixed it and purchased a new one that was adjustable for $100. Now my old one is the backup, and I don't mind bringing it to electronics group meetings.

However, this is a worthwhile iron to fix if the cost is not too great. The new fancier models have more features, but you really can't beat how durable and usable these old wellers are. While you're at it, you might as well get another tip or two.

^{Not affiliated with digikey, but they are a reasonable online supplier if you are in North America}

Answer 2

I have been repairing this Weller model since 1975. Carl Weller has 3 US Patents (1958-1965) for the Magnetic switch (Magnistat) technology, before TRIACS were invented and Electronic Temperature control was possible/introduced in the 1970s.

Some of the answers, previously provided here, have partial or INCORRECT information. One person lifted my PDF scan of Weller Tech Sheets and is now hosting on his web page.

This style of the Weller W-TCP series solder station (blue housing) was mfg. from 1970 to 1976, and for a US NAVY contract after 1976 for a couple of years. The irons are referred to as: TCP-1. The HEATER is WIRED-IN: part number, TC-208 (old HE-60). MAGNETIC (Magnistat) SWITCH: SW-60

In 1981, Weller switched to new PLUG-IN (EC-234) heaters for the TC-201P and TC-201T irons.

NOTE / REPAIR WARNING: Since 2003 (RoHS compliance/re-tooling), Weller has CHANGED the TCP/EC heaters: TC-208 (legacy wired-in) and EC-234 (plug-in). Weller SWAGGED the barrel on these heaters to a larger diameter. SO, NEW BA-60 Barrell Nut (2003 or later) MUST be purchased for heater replacements (TC-208 or EC-234).

TIPS: Weller PT series with magnetic ferrous alloy plugs on end of tips that determines tip temperature (engraved 7 means 700 F). These are the same tips used on current WTCPT model.

You can find Weller Tech Sheets (PDF scans from my document library) at: BAMA Mirror. Here is the WTCPL Tech Sheet http://bama.edebris.com/manuals/weller/wtcpl/

Weller at Apex, NC has parts and service, as well as larger dealers, such as: All-Spec.

Answer 3

Check the resistance of the element, it's probably failed. You might be able to get a replacement from Weller.

Answer 4

Answer found here.

Some Weller irons as part of the temperature control have a small spring loaded magnetic plate that the tip attracts. I have seen binding in the movement of the plate over time. If your iron is one of these, unscrew the end of the rod and carefully clean the tip and make sure that the mechanism works smoothly. I used to slide the tip in and out to make sure that the tip could attract the magnetic plate.

Answer 5

One issue with these irons is that the magnetic switch snapping on and off, connecting the 24 VAC power to the heater is inside the metal tube of the heater, all of which is in electrical contact with the item being soldered-ESD protection concerns obsoleted the irons for production use in many places and they just got dumped once better ESD-protected irons became available. A lot of them showed up at flea markets over the years after that.

The heater runs on 24 VAC. One smart idea I remember from QST magazine was intended to add a light to show when the switch turned the HEATER on rather than when power was on, applied to the internal transformer, regardless of the heater being on or off.

Measure the current the heater consumes (I think 2 amps, but am not sure). Add a resistor that would drop 2.1 volts of that 24 Volts (My calculations say roughly 1 ohm) inline and wire an LED across that. The LED is happy powered at 2.1 Volts, half the time, is off the other half of the time. The heater load limits total current inline so the LED in parallel with the resistor is happy. The LED current at 20 MA is minor power compared to the 2.1 Volt drop of the resistor, BUT you have 4.2 watts of heat to get rid of and should calculate a safety factor, probably use 7-10 Watt resistor.

The LED does not light on negative half-cycles but is not damaged. But the LED only comes on when the iron drawing current and in this case that is either on or off. A burnt-out heater will not light the LED.

Answer 6

Regarding Weller soldering stations that won't heat, I had this failure on my WCC100 adjustable-temperature soldering station that I have enjoyed through the years. It uses a different temperature control method than the WTCPL, so my remedy will not be directly applicable to yours, but my experience could be useful to people who have a failed WCC100. (The WCC100 uses a thermocouple temperature sensor and a triac to adjust the power to the heating element.) I recently noticed that both the electrolytic capacitors on the WCC100 circuit board had leaked. The two electrolytic capacitors are surface-mount parts in metal cans, having values of 47 microfarads and 2.2 microfarads. Rather than ordering exact replacements, I replaced each with like-valued capacitors I had on hand. The capacitors I installed had leads and were larger than the original capacitors. There is sufficient room on the board to do this. The replacement capacitors should be rated for at least 16 volts and should be installed with the same polarity as that of the ones removed. This repair did the trick, and the soldering station is functioning properly again. I suspect quite a few of the WCC100 soldering stations that have failed may have this problem.

Answer 7

The Weller was it at the time we were going to the moon. The most common failure in my history over the past 45 years is the thermostat which is located in the wands steel barrel. I plan to call around tomorrow and see if torrance electronics has parts. Torrance is old school and carries all kinds of things. (310) 328-2501. Ask for Old Guy or Grumpy. They go back far enough, and care enough, to get the answers. Otherwise, it's Ebay for mine tomorrow.

Test the two red leads for 25 A.C. Volts. If it is there then the tips open or the wand's wiring is open is open or it is the thermostat. In any event replace both parts since the other will just fail later.