Chosen Solution

Hi there, I bought a “Cleargrass” air quality tester from China:

Great device (while it worked), great build quality. See https://qingping.co/air-monitor/overview (Google translate helps with the Chinese) for more details. A few days ago, it started to make terrible noise:

I guess it’s an internal fan. The device has a particulate matter air quality sensor. The way it works is: sucks in air and counts particles via laser reflection. So it definitely has a fan that’s also visible here in the explosion chart and video:

The device looks really solid and has no visible screws. Two questions: Any idea how I might be able to open it? Is it glued together? Would that mean: put a hair dryer at the back of the device and try to pull off the lid on the back (see explosion chart) If I can open it, do I have a chance to fix the fan, as it seems to be a whole sensor module from the explosion chart. Would appreciate any help. It’s a great device but the noise is terrible. Would be a shame if I had to throw it away. Thanks, Holger No idea how to open it, I don’t even see a way to open it:

(And FYI: I sent the Chinese manufacturer an email, but no answer) —- Update: removed back lid:

Hello. Yesterday i tried to open it. Fan noise is horrible. But no luck. Update (03/22/2020)

Screews free feet Update (03/22/2020)

here was glue Update (06/07/2020) bolts are there

Update (03/22/2020) Just use car engine oil for fan. And noise should be gone.

please help to find compatible spare fan for this device. i’ve disassebled and assembled it, added silicon get as lub but fan does not spin - so device shows low values of pm2.5 - all other seems ok. now will try to attach photos wich shows how to make aluminium case removal easer. you just need to make few mm notch to take it back, not front

It’s probably a screwless case, this is preferable in assembly for cost and ease of assembly. Looking at the pictures I would take a best guess on where to try a prying tool. Probe around any seams you find and gently lift them. They should release if it’s a snap together case. Start with the back.

I have fixed mine by removing back lid , then with syringe and needle ive dripped small amount of oil for sewing machines directly to the center of the fan. With no need to disassemble the whole unit. Update (10/26/2020) @papikus U can use butter knife or something similar , and press it from the corners between monitor’s body and plastic backplate (lid) where charging port is, then slowly wiggle it to separate off back plate from rest of the body. Backplate has 4 hooks in corners that holds it to the body so do it slowly not to crack them.

https://freeimage.host/i/fE5Nvj

Just remove the back lid, and use some wd-40 on the fan, the noise gone like magic.

I opened from the back side. Remove the back plateMake two holes in order to remove stoppers (Check ilgiz ’s post)Push from the back and remove the metal coverRemove screws using screwdriver

I made 2 holes in the spot from the image above but no sign to get it out. You can see the holes in the image attached. Any ideas why it does not pull out?

I made this mess and still cannot open it. :(

https://www.youtube.com/watch?v=-5bt4u0Q… Disassembly