Newbie needs help

[TinyBlitzcrank]

Hello, I'm very new in electrical stuff, when it comes to electronics.

I bought a extraction fan for my house (extractor fan details: https://www.systemair.com/en/products/fans/duct-fans/circular-duct-fans/rvk?sku=36095#tech-specs-features )

I would like to controle the speed of the motor, in the website i bought the fan from it said it was dimmable, but after searching in the web i found out that i cant simply connect it to light dimmer. In the website of the manufacturer they sell a device that supposedly allows to set the speed (https://www.systemair.com/en/products/fans/accessories/electrical-accessories/speed-controllers/transformers/re?sku=5000) but it only offer 5 speeds and is more expensive than the fan. Also in my search i read that motors with capacitor cant be seed controlled (I don't know if its true).

my question is what type of circuit could control the speed, will the speed controller cause the fan life span to be shorter? 
I found a cheap Chinese speed controller for single phase motor in amazon, but I'm afraid it will hurt the motor of the fan. 

In the future I would like to be able to control the speed via my Arduino uno

I'm grateful for any help or links.

[BeBuLamar]

I think you're out of luck. The specs seems to indicate that you can vary the speed by varying the supplied voltage from 80V to 230V but the power must be sine wave. Any device that lower the voltage by chopping part of the sine wave wouldn't work (like a lamp dimmer).

[lakis70]

One idea is to use a variac if you have and note which voltages you will use, and order a transformer with some outputs that much your voltages, or a 1:1 transformer and a selector to select some capacitors to have some speeds like some cheap ceiling fans. I have one 30W i dont know if it is much difference for your 160W fan. Also look for the wall selektor for ceiling fans in factories

[Benta]

"after searching the web"
Right.
Perhaps it would be better to read the documentation from the manufacturer?
They even mention "thyristor control" is OK, aka Triac dimmer.

There's 1% correct information on "the web". The remaining 99% is BS. The problem is sorting out the 1%.