Let's just say that your kitchen won't get smoky if you have one of these bad boys!
Here's my KDK Solid State exhaust fan, model 25QPQ! I can't believe I just stated that! This fan has been lingering near the top of my ventilating fan wishlist since I was in grade school. I watched tons of videos from Japanese vent fan collectors back then, and I've always been fascinated by the unusual controls on the front panel of this fan. Almost nobody I watched demonstrated what this feature is for back then, and I think there's only 1 video which shows the automatic feature in action, and it was published quite recently.
From my limited research, I believe this fan was only available in 8" & 10" diameter. You could get them both from National or KDK, and you could choose whether you want black or orange colored blades. Blue & green might be an option, but I don't think I've seen any. There's also a variant of this fan with an indicator wheel instead of 2 indicator lamps on the lower right panel. I think I've read the original asking price of this fan somewhere, but I can't exactly put my finger on exactly how much this fan retailed for, it was definitely quite expensive though! That price got you the peak 70's Japanese electronics technology, and it's definitely a museum piece!
To be honest, I can't wrap my head around how this fan operates. There's a set-up procedure you have to follow after you plug this fan in, which is to turn the knob all the way clockwise & set it to auto, leave it to operate for 30 seconds, then slowly turn the knob counterclockwise until the control light turns on. Then you leave the fan alone for about 5 minutes, at which point, the setup process is complete & the fan shuts itself off, waiting for smoke to trigger the sensor. I thought the solid state thing allows you to reduce the speed of the fan, & the smoke sensor operates independently of it, but I think the knob is there to set a baseline air cleanliness level, or to put it simply, you help the fan learn how clean the air in the room it's in on average. My cluelessness with this fan doesn't stop there though, as there's also apparently a 2nd setting in the 'on' position which slows the fan down, and you can only get that slower speed after you set the auto function. In other words, this fan runs on full speed in both the 'on' setting if you haven't set the auto feature. There's also the electronically operated shutter, which I thought at first was operated via solenoid, but upon closer inspection on the mechanism which sits behind the motor, it looks like it works with a synchronous motor with gear reductions. Oh, there's also the fact that the shutter opens in different speeds depending on which speed you set the fan in at the 'on' function.
I think I can start to see steam coming off your head, but the interesting features don't stop there. If you set this fan on 'auto', it sits pretty waiting for you to make some sort of air pollution, at which point it turns itself on full speed. It runs for up to 5 minutes after all smoke/dust has been extracted to make sure the room is fully clear. In my demonstration of the 'auto' feature, I lit & then extinguished a match right on the sensor housing. The fan actually ran for around 7 minutes prior to shutting itself off, but I cut the video short.
I honestly still can't believe I have this fan in my collection! I used to think that I needed to import one from Japan, or buy one off of a collector once I get the chance to visit Japan, but I only spent 2 hours & a bit of gasoline to get my hands of this fan, and it was rather cheap too! Yes the black metal indicator panels have corroded a bit & the spinner nut is yellowed, but overall, this fan is in amazing shape!
#KDK #ExhaustFan
25 дек 2023
