LED downlights blowing prematurely

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kandjaja, Aug 19, 7:07am
I have 5 downlights on one circuit, switched one way. I have fitted led bulbs but they are starting to fail sfter two months. Any ideas?. Tia

john.s, Aug 19, 8:57am
Yes, you bought cheap no-name chinese ones off Trademe.

kandjaja, Aug 19, 9:00am
No, actually I bought Philips ones from a local electrical outlet for around $22 each. any further banal comments?

ryanm2, Aug 19, 9:05am
Are they screw type lamps replacing incandescent or MR16 (2 pins) type replacing halogen downlights.

kandjaja, Aug 19, 9:07am
They are ES27 base

ryanm2, Aug 19, 9:13am
The contact pins on your fittings will be bent back only just making contact, sometime working, sometimes not, sometimes arching which will blow any lamp inside. If it was me, I would just bite the bullet and replace with LED fittings, the issue will be solved forever.

kandjaja, Aug 19, 9:24am
With respect, have you seen this before? Being screw in fittings there is a single contact in the center, nothing to bend.

captaingraham, Aug 19, 10:58am
There are two contacts, one in the centre and one on the side. The side one will be faulty and need bending out a bit. Turn power off first!

kandjaja, Aug 19, 11:12am
Not on my fittings. One contact in the centre.
http://www.superlux.co.nz/products/?id=343&product=244

johotech, Aug 19, 8:27pm
Every light fitting has two contacts.

E27 lampholder contacts do bend from over-tightening and heat.

kam04, Aug 19, 9:39pm
This.

Sometimes they can be quite hard to see. Use a small screw driver to bend the side contact out only about 1mm. Us sparkies know this problem well. I used to have to do this for quite a few people. They did it themselves once I showed them how. As said above, turn the power off first!

mrploppy, Aug 19, 9:44pm
Check the fittings for heat transfer/ air flow. LED bulbs do generate heat just like standard light bulbs. The trouble is that standard light bulbs radiate their heat from the bulb, whereas LED bulbs use their base as a heat sink, and must have a reasonable air flow to keep them cool. Since downlight fittings are more prone to heat problems, LED bulbs will also fail from overheating if there is not sufficient air flow around their base.

vivac, Aug 20, 4:17am
Five electricians including me would beg to differ.

captaingraham, Aug 20, 5:05am
I know the problem. All that electricity is getting stuck inside the lamp because it can't get out again.

moby, Aug 20, 5:14am
+1 to that. I bought several noname GU10 LED lamps on TM and they didn't get 5% of their claimed 10,000 hours. Absolute rubbish.

ryanm2, Aug 20, 5:18am
every sparky sees this on a weekly basis.

mopeds, Aug 20, 5:45am
Even though they use much less power, LED's have a cooling requirement across the heat sink, if your old fittings prevent the cooling airflow the life expectancy will be dramatically reduced.

jane310567, Aug 20, 6:30am
keen to replace my MR16's with LED's but worried this may happen to us too with overheating. I can't afford to replace all fittings tho and they are a rectangular double fitting which I cant seem to find in LED's.

johotech, Aug 20, 6:47am
MR16 fittings already have plenty of ventilation built in for the 50W halogen lamps. LEDs designed for halogen replacement will not be a problem as they have built in air circulation. Look at quality LEDs like this http://tinyurl.com/o3qjuzp and you will see what I mean.

ryanm2, Aug 20, 7:07am

ryanm2, Aug 20, 7:09am
best to measure your ones (the outside measurements ) and hope these are similar or larger. I put some in the other week, pretty impressive.

john7891, Aug 20, 7:15am
As far as heat build is concerned what about the LED fittings (I read the box in Mitre 10) that say the insulation can cover the fitting. Wouldn't this shorten the life ?

johotech, Aug 20, 7:26am
There are plenty of fitting rated for insulation to cover them. It won't shorten the life when it is a correctly rated fitting and lamp, with the correctly rated insulation covering.

http://nzei.co.nz/wp-content/uploads/Downlight-FAQs-V6.pdf

jane310567, Aug 20, 8:34am
http://www.lightingplus.co.nz/lighting/recessed-lights/ceiling-halogen-12-volt/tango-twin-downlight-white.html
this is what we have in brushed chrome. Not sure if the replacement LED's can go into them. Really like the link to the fittings but not sure of size of cutout.

jane310567, Aug 20, 8:42am