Did you know about dust problem in 27" iMac?

[Trt740]

Hello,

I had a lot of questions in this topic - https://forums.macrumors.com/threads/imac-27-or-21.2122173/#post-26136334 and thankfully you guys helped me to choose better option. The thing is - I still don't know should I get 27" iMac. Does iMac still have a problem with dust in screen/under screen?

There are a lot of topic about this problem, even at Macrumors. Here you have example, what is it look like:

https://www.ifixit.com/Answers/View...+dust+in+the+screen+like+the+previous+models？

I made this poll to see if you guys and girls had to deal with this problem...

I have had a 2015 and 2017 iMac 27 retina and both have had the dust issues under the screen in the corners due to the fan. Apple is aware of the issue and the newly designed M1 version does not have a fan under the screen bezel( so the problem should end with that design). You can look on you tube and find a tutorial on how to clean it, but it will come back after a bunch of work. The kit has a cutting wheel and new adhesive.

 

[Trt740]

My understanding is that the newer iMacs have laminated screens. The LCD panel is bonded directly to the glass, with no gap between them. The lack of additional air gaps reduces the number of easily-reflective surfaces, and is part of how they obtain a richer color palate, etc. Therefore, I don't know how dust would get in between the two, unless it was bonded-in as a factory defect.

it is a known factory / design flaw

 

[Trt740]

I've used a lot of iMacs dating all the way back to the original iMac. I've never seen this issue. I suspect it happens more in extremely dusty environments like Schools though.

No it happens in a normal non dusty environment . This is a common issue with all iMac after a few years of use. it is micro dust that forms from gaps in the system, when the fan on the underside of the screen, forces dust under the white screen backing paper. It can only be seen on white screens.

 

[Trt740]

My 2011 iMac had a similar issue. Distinct marks like dust or dirt appeared inside the LG IPS part. Eventually I took the whole thing apart to prove there was no dirt. In my case, it was a localised cooling problem. Light leakage would also occur. It was outside its warranty in any case. Later iMacs had a different design, mine used magnets to attach the screen cover.

yours is the older design the newer intel iMacs have adhesive.

 

[jagolden]

I bought a refurbed 27” iMac in 2018. From day one it has been set up and running in my (unfinished) basement.
There is no dust under the screen.

 

[TwoH]

I have had a 2015 and 2017 iMac 27 retina and both have had the dust issues under the screen in the corners due to the fan. Apple is aware of the issue and the newly designed M1 version does not have a fan under the screen bezel( so the problem should end with that design). You can look on you tube and find a tutorial on how to clean it, but it will come back after a bunch of work. The kit has a cutting wheel and new adhesive.

My guy, the 2012-2020 iMacs don’t even have a fan under the bezel to begin with. The m1 does

 

[jagolden]

My guy, the 2012-2020 iMacs don’t even have a fan under the bezel to begin with. The m1 does

Was there a 27” M1? I can’t find one.

 

[TwoH]

Was there a 27” M1? I can’t find one.

No, there is only a 24”

 

[jagolden]

No, there is only a 24”

Yes, I thought so. Not sure what the M1 was doing here.

 

[Trt740]

My guy, the 2012-2020 iMacs don’t even have a fan under the bezel to begin with. The m1 does

I stand corrected. The fan intake is under the base of the screen. The air is drawn in under the screen as well as though the back near the ram, and micro dust builds up in the corners of the screen causing shadowing. This is per Apple. They have replace one of my screen and it did it again. This is not even a debatable issue. Heck 90+ people on this forum have this issue. Apple is well aware of the problem that's is part of the reason the newer iMacs do not use the venting system on the bottom of the screen in the same manner as the older intel iMacs. They do have dual fans on the bottom to cool the M1 chip. I bought my daughter one of the new M1 iMacs and the design is definitely different. So far no micro dust.

Thanks my guy for pointing out that nuonce

 

[Gudi]

Apple is well aware of the problem that's is part of the reason the newer iMacs do not use the venting system on the bottom of the screen in the same manner as the older intel iMacs. They do have dual fans on the bottom to cool the M1 chip. I bought my daughter one of the new M1 iMacs and the design is definitely different. So far no micro dust.

All-New iMac Features Stunning Design, Brilliant Display & Faster Performance
In the new design, the cover glass is fully laminated to the LCD and an anti-reflective coating is applied using a high-precision plasma deposition process. Every iMac display is individually color calibrated using an advanced spectroradiometer.

It must've been the 5mm edge iMac redesign of 2012 when Apple started laminating the front glass directly onto the LCD panel. This reduced reflections and made dust behind the screen impossible. The fan positioning has nothing to do with it. Now you know what happened 10 years ago!

 

[ProTruckDriver]

It's been almost 5 years now that I have had my iMac screen replaced with AppleCare. NO black smudges on the screen (Knock on wood). I vacuum the fan intake under the base of the screen when needed.
https://forums.macrumors.com/thread...en.2032995/page-2?post=25953002#post-25953002

 

[Nighttraine12]

It's been almost 5 years now that I have had my iMac screen replaced with AppleCare. NO black smudges on the screen (Knock on wood). I vacuum the fan intake under the base of the screen when needed.
https://forums.macrumors.com/thread...en.2032995/page-2?post=25953002#post-25953002

Thats great I wish I was that lucky. The smudges came back after my screen was replaced on my 2015 with Apple Care. I have bought the kit to cut the adhesive on my 2017 and clean the smudges but just have not had time to do it yet. I went to my local Apple store a few days back with an issue with my daughters mac air and a guy was getting his 27 inch screen replaced for this exact reason.

 

[Tridentine]

This is disappointing to see.

I purchased a 2019 iMac in 2020, and have had the display replaced 3x. Now that my AppleCare is no longer running they are reluctant to work with me. After 2 replacements they are claiming that it is the environment that the unit is in.

Here:

https://forums.macrumors.com/threads/dust-to-dust.2378027/?post=31905208#post-31905208

 

[Tridentine]

I have another meeting scheduled with Apple, they say that they are willing to replace the display again w/ a limited 90 day warrantee. I honestly don't want it. It has always been a defective product for me.

 

[vddobrev]

I have another meeting scheduled with Apple, they say that they are willing to replace the display again w/ a limited 90 day warrantee. I honestly don't want it. It has always been a defective product for me.

After I had the screen replaced on my 2015 27" iMac, I sold it. I did not want it in my life to deal with the issue again after some time.

 

[Trt740]

Well in my case it looks like very light shadowing in the corners of the bottom screen. I noticed it started when i had my display take longer to shut down ( going to sleep) meaning the systems fan running longer. I have since had it go to sleep sooner and this seem to stop the micro dust progression. With the 27 inch I really only notice it on a white screen and even then its light. It is just a design flaw. My iMac is in my kitchen and I change my furnace filter once a month so in my case it is not an environmental issue.

 

[Trt740]

All-New iMac Features Stunning Design, Brilliant Display & Faster Performance
In the new design, the cover glass is fully laminated to the LCD and an anti-reflective coating is applied using a high-precision plasma deposition process. Every iMac display is individually color calibrated using an advanced spectroradiometer.

It must've been the 5mm edge iMac redesign of 2012 when Apple started laminating the front glass directly onto the LCD panel. This reduced reflections and made dust behind the screen impossible. The fan positioning has nothing to do with it. Now you know what happened 10 years ago!

You are not correct there are repair kits on the internet for this problem and several youtube videos showing how to repair it and how it happened. The fan draws dust into the base of the screen and the micro dust infiltrates the white backing polarizing film of the screen. They did not seal the screens correctly. There is a design flaw in the screens themselves that allow dust inside the white backing polarizing film. The lCD is laminated however it still gets through.


Imac 2017 screen repair here.