Why isnt my boiler working, what is this and is it safe?
Discussion
So, i've got a boiler. A very old boiler, but it does the job.
The last few days i've noticed the pilot light keeps going out (reasons unknown), even when the heating is on, causing everything to stop working.
When i try and light it, it sometimes lights and sometimes doesnt.
Now, here's a pic;
To light it, you press the green square in, then press the black button to the right and it lights. Release the black one, and hold the green for 20 seconds, release and it should stay lit. Sometimes it does, sometimes it doesnt.
However, it seems ot have a lot to do with the piece of copper wiring you see in a circle. When the pilot is lit, it seems to trip out unless a piece of metal is touching it. This metal in this case is the cover, shown here;
As you can see, the cover slides to the back of the boiler. There's scratch marks on the right where part of the copper has clearly been rubbing against the cover for some time.
It seems to be that when the copper is not touching metal, it wont stay lit. When the metal cover and the copper break their contact, thats when the thing trips out.
All of this doesnt seem very normal or very safe to me, having bits of metal touching other bits of metal. Is it some sort of earth or something, and how should it work?
It still doesnt explain why the pilot wont light, sometimes, even with the metal touching the copper it lights, sometimes it doesnt, but this copper wire and the sliding cover underneath have clearly got something to do with it.
Hope this makes sense!
The last few days i've noticed the pilot light keeps going out (reasons unknown), even when the heating is on, causing everything to stop working.
When i try and light it, it sometimes lights and sometimes doesnt.
Now, here's a pic;
To light it, you press the green square in, then press the black button to the right and it lights. Release the black one, and hold the green for 20 seconds, release and it should stay lit. Sometimes it does, sometimes it doesnt.
However, it seems ot have a lot to do with the piece of copper wiring you see in a circle. When the pilot is lit, it seems to trip out unless a piece of metal is touching it. This metal in this case is the cover, shown here;
As you can see, the cover slides to the back of the boiler. There's scratch marks on the right where part of the copper has clearly been rubbing against the cover for some time.
It seems to be that when the copper is not touching metal, it wont stay lit. When the metal cover and the copper break their contact, thats when the thing trips out.
All of this doesnt seem very normal or very safe to me, having bits of metal touching other bits of metal. Is it some sort of earth or something, and how should it work?
It still doesnt explain why the pilot wont light, sometimes, even with the metal touching the copper it lights, sometimes it doesnt, but this copper wire and the sliding cover underneath have clearly got something to do with it.
Hope this makes sense!
Thermocouple. When the pilot light is burning it keeps the thermocouple warm and cosy. If the pilot light goes out for any reason the thermocouple cools and shuts off the gas (so no bag bangs when it is relit). If the thermocouple itself is feeling its age the gas is shut off until it is replaced - not a very expensive part usually.
The flaw in the above system is that you can't relight the gas while the thermocouple is cold and you can't get the thermocouple warm until the pilot is relit. To get round this the green button bypasses the thermocouple circuit so the pilot can be lit.
The flaw in the above system is that you can't relight the gas while the thermocouple is cold and you can't get the thermocouple warm until the pilot is relit. To get round this the green button bypasses the thermocouple circuit so the pilot can be lit.
I am not a boiler engineer, just a landlord who over the years have stood watching engineers servicing or repairing boilers.
Most gas appliances have a pilot light, which is initially lit by a spark passing across to light the gas. To keep the pilot light lit, there is an electronic flame failure device, the same that sits within the pilot light, and when the pilot light is lit, the flame magnetises the electrode, thereby releasing gas. When the pilot goes out, the electrode stops magnatising, thereby shutting off the gas supply.
You could check to see that the electrode tip is sat within the pilot flame, or simply replacing replace the flame failure electrode, Toolstation, Screwfix or any Plumbers Merchants should have the part.
I hope the above helps.
Most gas appliances have a pilot light, which is initially lit by a spark passing across to light the gas. To keep the pilot light lit, there is an electronic flame failure device, the same that sits within the pilot light, and when the pilot light is lit, the flame magnetises the electrode, thereby releasing gas. When the pilot goes out, the electrode stops magnatising, thereby shutting off the gas supply.
You could check to see that the electrode tip is sat within the pilot flame, or simply replacing replace the flame failure electrode, Toolstation, Screwfix or any Plumbers Merchants should have the part.
I hope the above helps.
The thermocouple produces a very small current when the tip is heated. It may be that it's loose at the gas-valve and when it's pushed by the sliding case it makes a better connection. Small resistances are crucial when dealing with current this small. Check it's tight at the gas valve end (The bit with the buttons on) if that fails it's probably knackered. New thermocouple isn't expensive. I wouldn't worry about the touching. That won't worry it except if it's lose. The amount of current is next to bugger-all. The REASON it's touching is because a universal thermocouple has been used rather than one the correct length..not a big deal.
Nice idea.I'm going to venture that you should call a local Corgi man out to look at it, since if there's one thing more dangerous than 'bits of metal touching other bits of metal', it's 'people touching gas appliances wot don't understand 'em proper'.
Accordingly, I'd probably call a man out myself even though I have a pretty good idea exactly what he'd need to do - just in case an experienced eye spots something I'd miss.
Accordingly, I'd probably call a man out myself even though I have a pretty good idea exactly what he'd need to do - just in case an experienced eye spots something I'd miss.
If it's an old non-condensing boiler you might save yourself some money by replacing it at the start of winter.
I spent heaps keeping my 20 year old oil burner going and when it was finally replaced found my fuel consumption more than halved. It's paid for itself in two or three years and the house is warm.
I spent heaps keeping my 20 year old oil burner going and when it was finally replaced found my fuel consumption more than halved. It's paid for itself in two or three years and the house is warm.
Piepiepie said:
Why would the pilot be going out without reason? Its happening pretty much a daily basis now, even when running.
The pilot is not going out without a reason. The most likely cause is the thermocouple is loose, breaking down or the pilot injector is blocked,if you are unlucky the gas valve may be shot.Get a man in to replace the thermocouple and give it a service. Oh make shure he coils the thermocoupe neatly if he uses on of the incorrect length.Piepiepie said:
Why would the pilot be going out without reason? Its happening pretty much a daily basis now, even when running.
I despair every time I read one of these threads. You clearly aren't a gas engineer so stop being so tight and call one out. I'm all for DIY, but there are certain things which are best left to the professionals.CDP said:
If it's an old non-condensing boiler you might save yourself some money by replacing it at the start of winter.
I spent heaps keeping my 20 year old oil burner going and when it was finally replaced found my fuel consumption more than halved. It's paid for itself in two or three years and the house is warm.
I got my mum a new boiler after a national gas firm..cough..cough..tried to make out the old one was knackered. It wasn't, they'd just done a few things to stop it working. Still, they saw teh error of their ways & replaced it for cost price so result there I spent heaps keeping my 20 year old oil burner going and when it was finally replaced found my fuel consumption more than halved. It's paid for itself in two or three years and the house is warm.
The new boiler has more than halved the bills so I'd go along with the above.mybrainhurts said:
MJG280 said:
I'm into DIY and am very tightarsed. Whilst I could fix a thermocouple easily I wont. Get a Gas Safe Registered gas man in to fix it.
You lazy git. C'est un piece de piss. I've replaced at least six on mine.Saying that I've just replaced my 25 year old gravity boiler with a worcester bosch combi and paid £550 for a gas safe plumber to fit. Not bad for 2 and a bit days work.
The difference the new boiler has made is amazing. I'm gutted about the old one as there wasn't anything wrong with it other than a carbon dioxide leak.
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