House light too hot

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mb82

223 posts

Master Geek

#206199 13-Dec-2016 21:42

I have come across a halogen house ceiling light of a friend which appears too have been too hot. The paint behind where the bulb sits appears to have melted and the wire hole through the timber behind light looks black.

Facts:

Light labelled 200w max

200w tube style (contact each end) bulb installed

Bigger light of same style in another room labelled 250w and has 250w bulb. So I assume light is labelled correctly. Light in other room rarely used so if it was running too hot probably hasn't been used enough to cause damage.

Not sure if running too hot at the moment or what I am seeing is from the past

Suspect bulb has been replaced at some stage

Suspect owner would have noticed melted paint when replacing bulb

1) Are bulbs ever labelled as the wrong wattage? Can bulbs fail and draw more power than they should?

2) Can I calculate bulb wattage without measuring current draw?

3) Could incorrect wiring cause this?

4) Does it matter which way up a halogen bulb is installed (One side has glass nipple from when it was made)

5) What else could cause this?

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#1687393 13-Dec-2016 21:48

Those lamps generate CRAP LOADS of heat. What you're seeing is pretty much as expected, although if it was poorly installed there might be an issue that needs attention ASAP.

larknz

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#1687397 13-Dec-2016 21:52

Does the light fitting have a reflector fitted. These are often used to reduce the amount of heat behind the fitting. If it doesn't then someone may have removed it. If this is the case the fitting should not be used.
Does the fitting have a label stating maximum lamp wattage. A 200w lamp produces a lot of heat and I would expect some sort heat shielding in the fitting.

mb82

223 posts

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#1687417 13-Dec-2016 22:40

Picture=thousand words

andrewNZ

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#1687419 13-Dec-2016 22:52

Looks pretty standard to me. They are horrible fittings, and are notorious for cooking themselves and the wiring they're connected to.

These are prime candidates for some kind of LED replacement. The payback would be quite quick I'd think.

mb82

223 posts

Master Geek

#1687485 14-Dec-2016 07:27

Not disagreeing but if this is normal it seems crazy that this is considered acceptable. Especially with todays health and safety.

richms

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#1687487 14-Dec-2016 07:38

They are notorious for people putting 500W lamps into them, since that is all you could get easily for quite some time.

Richard rich.ms

robjg63

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#1687492 14-Dec-2016 07:43

250w is a vast amount of potential heat in a small area!
Would not be happy with one of those light fittings in my house.

Some of those flat panel wall mounted 'heaters' are 400w and that heat is for trying to warm up a room, and the heat is disputed over a roughly 1m sq area.

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richms

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#1687495 14-Dec-2016 07:46

robjg63: 250w is a vast amount of potential heat in a small area!
Would not be happy with one of those light fittings in my house.

Some of those flat panel wall mounted 'heaters' are 400w and that heat is for trying to warm up a room, and the heat is disputed over a roughly 1m sq area.

Not sure they are that large, but even at half square meter they still manage to cook the wall up behind them quite well.

Richard rich.ms

trig42

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#1687522 14-Dec-2016 09:10

A 200W bulb in one of those is overkill IMO.

That is a crapload of light (and heat). It is possible someone had put something too big in it at some point though, it would have been noticeable (smell at least).

robjg63

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#1687525 14-Dec-2016 09:17

Its actually quite surprising they have a sticker that says 200w.

Most of those pressed metal light fittings with a glass cover normally seem to have a 60w or 75w rating at most for normal incandescent bulbs.

There are certainly some quite good LED lights on the market now. Would save a lot of electricity and be very cool (temperature that is).

Nothing is impossible for the man who doesn't have to do it himself - A. H. Weiler

richms

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#1687540 14-Dec-2016 09:20

There are some terrible cheap LED oyster lights. Avoid them. One a friend had put in was a strip of LED tape around the edge. 3 months in and some are already starting to dim out and the colour is terrible from them, looks almost pinky peach now.

Richard rich.ms

Oriphix

523 posts

Ultimate Geek

#1687549 14-Dec-2016 09:35

200W is a lot to pay in terms of electricity cost.

No topic, I would suggest to be on the safe side to replace that whole light fitting. The reason being you only see the surface at this point not sure what damage the heat could / would have done at the back (melted wires perhaps?).

You can pick one up at bunnings or miter10 for pretty cheap. LED is a good way to go to get a brighter light at lower watt

mb82

223 posts

Master Geek

#1688981 14-Dec-2016 22:23

andrewNZ: Looks pretty standard to me. They are horrible fittings, and are notorious for cooking themselves and the wiring they're connected to.

How are these 'horrible fittings' legal? I am surprised to hear this is considered normal. Would not want to go away for the weekend and leave it on, it would probably burn the house down?

Batman

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#1689046 15-Dec-2016 07:06

There are no "energy efficient" alternative tube bulbs are there?

sparkz25

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#1689208 15-Dec-2016 10:38

i would replace this light, looks as if its already done some damage, i have replaced a few of these over the years and found 2 where a client had put a 500w lamp in the fitting when it was only rated to 200w and it literally burnt the paper off the gib and melted all the wireing in the behind the fitting, it was lucky that he called us to repair the fitting and convince him to replace the fiting as the gib started to crumble away as we pulled it down and in some places the wires were exposed

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