I didn't open the heat gun, I had absolutely no reason to open it.

Don't do that it would void any guarantee of the tool. Doesn't is say in the operators manual, or is there a parts diagram?

 

Don't do that it would void any guarantee of the tool. Doesn't is say in the operators manual, or is there a parts diagram?

I really don't care about warranties, I never cared. Really. It's not about that.
No, the manual is advising you for safety stuff, mostly. But not the circuit schematic, like in the old manuals.
I will take it apart and back engineer it as much as I can.

 

So... take it with precaution.
Some tracks may not be correct, I only inspect it visually, and not by continuity. Also, if some tracks are going under the IC, I didnt check it.
Some resistor values might not be correct (those blue resistors with 5 bands that you can read both ways and get different values). I used my best judgement in reading them.
The circuit I draw here is flipped/mirrored and rotated 180 degree, for the opamp to stay in normal position. On the board is staying upside down. I had to flip it, to match the components on the other side. I hope you get it. Also, the opamp here is having some black splash on it, that i remove it later to read its name, and see clearly its top marking, one single line, which is exactly under that splash.
I'm not completely sure if that is an opamp. I only read the last numbers on the cip: 58. I think I can see a 3 before 58 but extremely erased. If it had an LM before the numbers, it is completely erased. I think they used a "used" IC, but it is working fine so, I'm not complaining. The positive pin 8, is very weirdly connected.
Please make any rectifications you may think, and make this circuit make more sense. For me, it has no sense now. Its gibberish. I leave the nicrome wire unconnected in my drawing, because I can not see visually or get any continuity from its endings, probably because in circuit measuring. I measured it though and got some values, see top right corner.
That 220V long switcher is having 4 steps, but 5 lines of pins on the board.
All the diodes are pointing correct, I triple check it.
The wire colors match the ones in reality.
My guess, this entire circuit is working with only 110V, meaning, half of the 220V, only half of the sine wave. I was looking on D4, those 4 diodes. They look like a rectifying bridge but all they do is powering that motor, at 110V? really? ok... and if we take only 1 sense of the current, through the blue wire enters and is coming back through the white wire, that is variated through that triac. But there is the other wire, the red wire as well. Maybe... the other half of the wave is comming through it and back through the white wire? And how much you lower the value of that triac, more current is passing through it, and less current through the motor, so the speed decreases. It is how I see it and makes --some--- sense of this circuit. That OUT 1 of the opamp is having a diode directly opposing anything is coming out of it. That is a very weird part, unless that is a special circuit variant of the opamp. I only know the best, the comparator circuit of the opamp. Haha. But this might be something from the opamp variation of its functionality? OR... maybe he didnt need its output? Is beyond me, totally. Again, I really hope that is an opamp and not something else that terminates in xxxxx58.

Also a summary view of it's internals:

Also a close up on the IC inscriptions.

 

That doesn't answer the question or at least not my question. I'll ask again, what type of blower device is on the motor to push the air? A fan, a turbine, or what? Remember our discussion in your other thread where you were using a fan?

 

Ok, the blower itself is a very new design and probably a prototype. I for once, I never seen something like this before. I like it, since it works. I'm not an expert in blowers or fans either. Thats why i am easily impressed.
My impression of it's functionality:
You see that dreptunghiular hole in the black case? That is the sucking air hole. The blades are somewhat visible in the picture, but they are inside, like a cone, attached to the motor ax.

Inside the metal tube, we see a black plastic round case, with static blades inside it. That is an intriguing design. This case is not moving, it is a structural piece.

When is assembled, you can see the dreptunghiular sucking air hole very clearly. It is sucking the air from around the metal tube, while pushing the air inside the tube out. It is my interpretation of what I am seeing.
It is a very smart design, I like it.

This is the rotor, viewed from the front, and is like a disc. Behind the disk are the blades. You can see some little bumps behind this disk.
On the front of the disk you can see a white splashed round shape. That is solder that was sucked in and stopped by this disk. It can be very easy removed, I already removed some of it as you can see from the image.

 

Wow that is different! Kind of like the turbine compressor wheels in a jet engine. Thank you for showing it.

Where did the solder splashes come from?

 

Where did the solder splashes come from?

From 2 motherboards and several other small circuit boards. In total...like 8 boards I think.
I work it quite a while.

 

Either you have the heat gun too close to those boards or that is a really hard sucking heat gun! I'd be putting a filter over the air intake.