Glow-worm spacesaver 38 pilot light problem

[granty]

My glow-worm spacesaver 38 (approx 20yrs old) has a problem with keeping the pilot light on. I can light it with the ignition button and hold the valve in for about 1min then let go on it goes out. At this point it is supposed to be stable and i should turn valve to "on" position but as soon as i depress the valve, the pilot flame goes out. I have or do not know how to change the thermocouple.
Any suggestions folks?

Best Regards
Grant

 

[gas4you]

You will have to get someone in then as this is going to need a new thermocouple

 

[granty]

Job done myself. Replace the thermocouple with a universal pack from screwfix. Re-aligned the spark electrode and job done. Quick hoover and big smile on face.

 

[funyfeet]

Hi Granty

I have the same problem that you had and I was hoping that you could confirm a couple of things for me.

1) Is the thermocouple that you replaced the piece of wire that generates the spark and is bent into the pilot flame?

2) Is this the the replacement thermocouple that you purchased?

http://www.screwfix.com/prods/16098/Plumbing/Boilers-and-Accs/Super-Universal-Thermocouple#

If anyone else is reading this are they able to confirm that the pilot light when lit, heats up a thermocouple that keeps the gas flowing? I have a Glow-worm Spacesaver 38. The only reason that I have my doubts is because there only seems to be one electrical connection to it. Does the outer casing form the other connection?

Many thanks for any help that you can give.

 

[granty]

Hi funnyfeet, The thermocouple is the element that is placed so that the tip is in the pilot flame. Once hot, it will open the gas valve thus allowing the gas to flow. My thermocouple was faulty (wear and tear) and was replaced with the one from screw fix. This is a universal part as it comes with various attachments you require to install it for different brands of boiler. If you have the same boiler then this is indeed the part you want.
The spark electrode is the right angled looking wire which is about 1cm away from the thermocouple tip. A spark will conduct between the 2 metals causing the pilot flame to light. Once the thermocouple is at the correct temperature, the valve will open.
Even though the thermocouple tip looks red hot, it may not be sending the correct electrical reading to the valve hence failure to stay lit.

If the thermocouple and spark electrode is positioned incorrectly, the spark could spark somewhere else in the boiler. ie against the case if the sleeving is worn etc. Make sure the spark is coming from the right angled piece of wire and zapping the tip of the thermocouple.

I am not a plumber or gas man so be very carefull when doing your own DIY. Thermocouple was a piece of **** to change though. Good luck.