Failing halogen downlighters

[felix01]

Hi,

I'm a newbie here, and definitely no electrician so please go easy on me... about a year ago we had 15 MR16 50W recessed halogen downlighters fitted in our kitchen/diner. Since then we've had 7 bulbs fail, which seemed very much on the high side (is it?). More worryingly, in the last few weeks, I've had 3 more fail and I found the problem wasn't the bulb but the fitting. On one it looked as if the bare end of the wire had snapped, the ceramic fittings all looked in bad condition,with sooty deposits all over their innards. I can't tell for sure what rating the fittings are but does it sound as if they're too low rated? Don't know if it means anything but there's "25. 106/5" stamped on the bottom of the ceramic bit. Also worried that the wires might be overheating - I read elsewhere on this forum that they should be heat shielded?

Anybody any advice before I complain to our electrician?

Thanks!

 

[daytona]

are the lamps left on for extended periods?

are any of the clips from the downlights missing,causing the 12v wires to touch the lamp?

what make are they?

as for bulbs blowing,ten in a year doesnt sound too bad really.when you say low voltage,i assume you mean 12v

 

[333rocky333]

Seems like the lamp heat has damaged the holders , you may need to get new holders fitted or maybe new fittings.

Sometimes it is not best to use 50 watt lamps if fittings are constantly on.

you can also get lamps that prevent heat going back into the fitting, but it sounds like the damage has been done

 

[felix01]

are the lamps left on for extended periods?

are any of the clips from the downlights missing,causing the 12v wires to touch the lamp?

what make are they?

as for bulbs blowing,ten in a year doesnt sound too bad really.when you say low voltage,i assume you mean 12v

Depends what you mean by extended periods - they can be on for a few hours at a time, we spend quite a lot of time in there.

No clips missing, but the wires coil up into the recess so I guess it's not impossible that the wires were touching the back of the bulb. I can't really see how you can guarantee preventing this since there has to be enough slack wire to allow you to remove/fit the bulbs and it's got to go somewhere? Should there be some sort of protection on the wires - there isn't at the moment?

As for the voltage of the wires, I've no idea how I can tell. they're just thin white wires. I said I wasn't an electrician

 

[daytona]

a few hours at a time is ok mate.
where did you get the fiitings from and what brand of lamps are you using?

do they tend to blow when you switch them on?

how many switches serving them?

 

[felix01]

a few hours at a time is ok mate.
where did you get the fiitings from and what brand of lamps are you using?

do they tend to blow when you switch them on?

how many switches serving them?

Don't know what make the fittings are, I trusted our builder's electrician . The bulbs the electrician fitted were Alutech - as they've blown we've been using cheapo B&Q ones (which so far haven't lasted too badly).

I've never actually seen one blow so can't tell if I've been really unlucky not to see it or if they're just going when I turn them on (though haven't seen one blow the way a conventional bulb does).

We've got 2 double switches: at one end a dimmer for the diner bit and an ordinary switch for the kitchen, then the opposite arrangement at the other end (if that makes sense).

 

[333rocky333]

That wire is high temp and no additional protection is required,

If the fittings are totally enclosed, they were maybe designed for cool fit lamps /aluminium.

These throw the heat forward rather than back into the fitting

This would have been in the instructions

If standard m16 were used these will overheat the fittings and even damage the high temp wire and lampholder.

 

[daytona]

a few hours at a time is ok mate.
where did you get the fiitings from and what brand of lamps are you using?

do they tend to blow when you switch them on?

how many switches serving them?

Don't know what make the fittings are, I trusted our builder's electrician . The bulbs the electrician fitted were Alutech - as they've blown we've been using cheapo B&Q ones (which so far haven't lasted too badly).

I've never actually seen one blow so can't tell if I've been really unlucky not to see it or if they're just going when I turn them on (though haven't seen one blow the way a conventional bulb does).

We've got 2 double switches: at one end a dimmer for the diner bit and an ordinary switch for the kitchen, then the opposite arrangement at the other end (if that makes sense).

cheap lamps will give you problems im afraid.use reputable ones(osram)etc
the dimmer maybe causing you problems.is it suitably rated and does it dim 12v lighting.if your confident enough,unscrew it and have a look.

 

[333rocky333]

You have then took out the right COOLFIT lamps and replaced with WRONG lamps
Now the holders are damaged and possibly the fire rating material within the fitting has now closed up causing the fitting to overheat.

The fittings fire rating material is once damaged not repairable

This would have been in the instructions

 

[felix01]

You have then took out the right COOLFIT lamps and replaced with WRONG lamps
Now the holders are damaged and possibly the fire rating material within the fitting has now closed up causing the fitting to overheat.

The fittings fire rating material is once damaged not repairable

This would have been in the instructions

OK you've lost me now... are my original Alutech bulbs coolfit? They are "M258 EXN" if that means anything. As for the B&Q ones, how do I know they are wrong? they have "cool beam" printed on them for what it's worth. I had no instructions with the lights - didn't realise I might need them!

 

[333rocky333]

As I said earlier

The fittings sound fire rated , they limit the heat through the back

Excess heat inside will close the back up sealing it to prevent fire above

Once sealed they are no good anymore.
As no heat will escape burning up wire and holder

These fittings require Aluminium back lamps that prevent that and throw the heat forward. COOL FIT LAMPS

By putting standard lamps in too much heat will be going back in to the fitting

You now say you have fitted COOL BEAM
these are even WORSE these are for lighting close objects without the beam heat damaging, ie paintings etc
These work by forcing heat BACK into the fitting
The opposite to what you want
YOU have now made the situation worse

 

[333rocky333]

Ge alutech lamps
Are one of the leaders for aluminium lamps
The cost of them is about £2.99 each
The rated life is 3000 to 4000 hours

 

[felix01]

As I said earlier

The fittings sound fire rated , they limit the heat through the back

Excess heat inside will close the back up sealing it to prevent fire above

Once sealed they are no good anymore.
As no heat will escape burning up wire and holder

These fittings require Aluminium back lamps that prevent that and throw the heat forward. COOL FIT LAMPS

By putting standard lamps in too much heat will be going back in to the fitting

You now say you have fitted COOL BEAM
these are even WORSE these are for lighting close objects without the beam heat damaging, ie paintings etc
These work by forcing heat BACK into the fitting
The opposite to what you want
YOU have now made the situation worse

OK, OK, no need to shout. If that's the case, how can I best salvage the situation? Obviously replace my B&Q bulbs first - having googled "coolfit MR16" i see there are a few around. Then, should it be just a case of replacing the actual ceramic fittings for the ones that have had the wrong bulbs in (i.e. the bit the bulb plugs into) or would it be more drastic than that?

Thanks

 

[333rocky333]

Seems like the lamp heat has damaged the holders , you may need to get new holders fitted or maybe new fittings.

Sometimes it is not best to use 50 watt lamps if fittings are constantly on.

you can also get lamps that prevent heat going back into the fitting, but it sounds like the damage has been done

 

[333rocky333]

Now the holders are damaged and possibly the fire rating material within the fitting has now closed up causing the fitting to overheat.

The fittings fire rating material is once damaged not repairable