Replacing LED chip on ceiling light.

[BobSout]

I have bought new chips as per photo. Does it need to be held in place with insulating glue, and should I solder between the bare areas as per the old one not removed yet? Thanks for any help.

 

[Avo Mk8]

I would imagine "heat sink compound" or "thermal paste", not glue. E.g:

RS PRO Metal Oxide Thermal Paste, 0.65W/m·K | RS

uk.rs-online.com

 

[BobSout]

I would imagine "heat sink compound" or "thermal paste", not glue. E.g:

RS PRO Metal Oxide Thermal Paste, 0.65W/m·K | RS

uk.rs-online.com

Thanks Avo, that makes sense.

 

[Avo Mk8]

I have bought new chips as per photo. Does it need to be held in place with insulating glue, and should I solder between the bare areas as per the old one not removed yet?

I'm intrigued that your original COB led has an extra pair of pads to which the wires are soldered. They seem to be labelled + and - as the others, so I guess you just move the wires a little to match up with the existing pads on the replacement LED. Remember which wire is + and -, to ensure the connections are put the right way round on the new one!

You don't need to connect the same polarity pads together, as I think they are connected in the board.

Re the use of thermal compound, although not good practice, if the paste on the old LED has not dried out, and is still very 'squidgy', you could scrape as much as possible off the old LED and put it on the back of the new one. However good thermal connection is important for the survival of the LED.

The diameter of your original LED chip seems smaller than on your replacement, suggesting the new one might possibly be a higher wattage (is it 7W?). If they are not the same power, the supply circuit may struggle/misbehave?

Good luck with the repair.

 

[BobSout]

Thanks very much for that. I'll get some thermal paste and have a go. If it works, will save 100's of £. We have 6 matching ceiling lights which are no longer available, so replacing one would mean replacing all!

 

[brianmoooore]

We have 6 matching ceiling lights which are no longer available, so replacing one would mean replacing all!

Which is why I avoid integrated LED fittings as much as possible.

 

[BobSout]

It worked . Many thanks for the helpful advice.