937D+ Hakko Clone Glows Red Hot Problem

[nation]

Dear All

The heating element on my 937D+ broke so I order a replacement iron. This is what happens when I plug the new iron into the station:

- The temperature gauge on the station stays at 1.
- The iron heats up quickly as usual but doesn't stop at the set temperature. It continues to heat until it glows red.
- The temperature gauge on the station slowly starts increasing a few digits at a time.

Is this a problem with the iron handle or the station?

I suspect it may some sort of problem with the wiring on the handle being mixed up and came across the video below where the guy starts talking at 50 seconds about the pinouts on the iron. Could this be my problem?

[.rpv]

There are 2 variants for that 907 handle, one with thermocouple and one with a ptc as temp sensing method, on the video says that the heater resistance it's 14ohms and for the thermocouple it's 2 ohms (it should be less, it's basically a short); for the second variant the resistance of the heater it's around 4ohms and the ptc resistance it's around 40ohms at room temp (it will change with temp, so you can expect more resistance). So maybe you are using the wrong handle for your station.

[nation]

Thanks .rpv. You're probably right, wrong handle. Someone in the comments section of the video said they had a similar problem. Wonder if there's any modification to this new handle I can do to make it work?

[.rpv]

Thanks .rpv. You're probably right, wrong handle. Someone in the comments section of the video said they had a similar problem. Wonder if there's any modification to this new handle I can do to make it work?

You can buy just the ceramic element which includes the temp sensor and replace it on your handle. For the ptc based element it's the model A1321 (cost around 2-3usd con aliexpress/ebay), but I haven't idea what's the thermocouple based model is.

You need to be sure what's the element that you station requires, on the hakko webpage says that the 936 station uses the ptc based one (A1321) but who knows on the clone, the easy way it's using a multimeter on the handle that your station includes and try to check the resistance of the temp sensor: 2ohm or less (probably more close to zero) it's a thermocouple one, 40ohm or more it's a ptc one.