Anyone repaired Ionmax ION390? I have extra screws :(

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Hi all,

Re-assembling a Ionmax ION390 air purifier after removing the top LCD control panel, I seem to have 2 extra screws that I, for the life of me, cannot see where they go. I've taken a couple of pictures, buuuuut there's always that one picture you need, but you didn't take :/.

I know it's a long-shot but has anyone repaired this before would have an idea?

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Not much luck with the screws, but it seems I have another issue. I noticed some legs were broken from what I assume is the LED backlight(?). Does anyone know the name of this part, whether it can be replaced or whether the piece I have is universal (ie I can get from Aliexpress)?

[stj]

lcd backlight is a good search term, i'v seen them but you need to know the size in mm.
or you could try drilling out the leds and replacing them using clear glue/resin
nothing to lose really

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Thanks for the reply STJ

I've been looking around but haven't much luck finding the same style. I'm not too sure how they're designed either, or what all the dots do. Are the dots the LEDS or does the sheet just distribute the light? I'm assuming the dots aren't the LEDs but I'm really unsure of how it's constructed. It looks like transparent acrylic block layered with transparent film that has dots, layered with another layer of white film (I can only assume its to diffuse the light?)

What sort of LEDs are used in the panel?

I've taken some measurements of the panel in case anyone knows of a potential replacement off the top of their heads.

[EDIT] Added more images. Had a closer look, looks like the LEDs enter into the acrylic piece though it appears to be domed, the remnants of the old LED seem to have a flat surface. Any clues what they might have used here?

[stj]

the dits are a defuser pattern,
they usually just use 3mm leds

[redwire]

I would say it used wide angle square LED's crazy glued/tucked into the notches, what size are they?
They come in 2x3x4mm or bigger longer like 2x3x7mm. You want the ones with the LED die up close to the end, not way back in the plastic = wide angle. Like this Aliexpress kind of thing.
It looks like the cutout is for a 3mm T-1 LED. They just glue them in.

[Widget]

Hey redwire, thanks for the reply . I think you may be right. I feel they are the square/rectangle shaped LED bulbs, like you've linked but likely clear Blue coloured.

I used some digital calipers and the measurements I got were, 2.7mm thick for acryclic, the hole is 3mm wide, 4mm deep & it looks to be 2mm thick, which match the dimensions in the link you posted.

Visually it looks like it take the domed (T1?) bulb, but upon inspection, it looks like the LED in there has a flat square shaped. I used some tweezers and was able to put them into the top of the dome and it went down, so it didn't appear there was any casing in that section if that makes sense (see pics). Also wondering if it's worth trying to find those leds in 'ultra bright'? Not sure how much light is produced at a wave-length of 460-465NM

If the old LEDs are glued in, do you reckon solvents (IPA or Acetone) would break down the glue?

[redwire]

Sometimes it's higher risk to do a perfect repair and I settle on something good enough.
You can try take a dental pick and scrape out the old glue without scratching the edges...
Acetone is the best solvent for cyanoacrylate, but if it eats the backlight diffuser plastics... as it does eat acrylic plastics... the damage and mess gets worse.

If an LED dry fits, then I would just glue in the 3mm or square LED and keep the repair simple. White/blue LEDs are crazy bright as they are, to get more brightness, using more current for them would take a resistor change on the board.

[Widget]

Originally Posted by redwire

You can try take a dental pick and scrape out the old glue without scratching the edges...
Acetone is the best solvent for cyanoacrylate, but if it eats the backlight diffuser plastics... as it does eat acrylic plastics... the damage and mess gets worse.

If an LED dry fits, then I would just glue in the 3mm or square LED and keep the repair simple. White/blue LEDs are crazy bright as they are, to get more brightness, using more current for them would take a resistor change on the board.

Thanks for the feedback redwire . You're right about the Acetone, good suggestion. I'll try dry-picking it out, see if I can do it that way.

[sam_sam_sam]

Originally Posted by redwire

I would say it used wide angle square LED's crazy glued/tucked into the notches, what size are they?
They come in 2x3x4mm or bigger longer like 2x3x7mm. You want the ones with the LED die up close to the end, not way back in the plastic = wide angle. Like this Aliexpress kind of thing.
It looks like the cutout is for a 3mm T-1 LED. They just glue them in.

Thanks for sharing this link I have need some several times and could have used some to repair some back light for displays but luckily I have several replacement controller boards for my desoldering station so have not been desperate enough to ask for help finding them yet