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Mend Johnson & Starley J25-32 Mk3 modair flow Replace Hot Air

How do I replace thermocouple on Johnson & starley J25-32 Mk3 modair flow?

This thermocouple is for the hot air central heating. The thermo for the hot water is OK. When I light the pilot light and take my finger off the button after the required time, the pilot light does not stay on. The pilot light seems healthy enough. I've recently been advised by this site that firstly it may be a thermcouple problem. My questions are... What part number do I need or or they standard. How do I fit the part. And lastly - say on a scale of 1 to 10 how easy is the job for an average DIY person. Thanks in advance.

JAY
October 2008
Yas. I've had my thermocouple replaced and need some advice regarding service. I've posted another Q regarding servicing my system. Would appreciate you reading it and will take your advice.
Thanks in advance.

JAY
October 2008
Thank you
you are a rare breed for a pleasant reply
If you got a corgi engineer make sure he is registered for warm air element
This is a open flue appliance and for safety sake should be service checked once a year

yas
October 2008
Thanks Yas. Now I know you are corgi registered I've taken your first advice and not attempting a DIY repair.
I've got a corgi registered repair man coming out on Monday. Thanks again.

Jay
October 2008
Yep i am corgi registered
Cant remember the configuration of pilot assy. on top of my head
The HE element is if to replace the successfully means you have to break into the gas supply
On some models it is a simple case of unscrewing from the front pilot housing and the gas valve
Part required is a standard Honeywell Q309A 36'' thermocouple or alternative

yas
October 2008
Please get a trained, competent and qualified engineer to do this job. Warm air units are not something to do a DIY job on. They can be VERY dangerous.

M
October 2008
YAS. Thanks for reading my question but when I see health & safety mentioned I am a bit wary. Example... we have a wallclock in work, when the clocks went forward 1 hour nobody was allowed to take the clock down and move the fingers forward 1 hour on the grounds of health & safety. We waited 2 weeks for a maintenance guy trained in this job to adjust the time.
Sometimes its just common sense. Gas and DIY do not mix, but if the job entails just unscrewing an old part off and just screwing a new part on then I may be competent, I dont know, thats why I'm enquiring on this website. Anything beyond this I would get a qualified man to do it. I do not mess about with gas ( or electrics ) I can look at a job and know right away if I can do it or not. I would not " Give it a try " and maybe get in over my head. You dont say if you are a qualified corgi trained gas fitter, if you are then I would take your advice but if you are not and know nothing about the job and simply see a job as a health & safety issue then I'm not too sure about your advice.

JAY
October 2008
On the grounds of health and safety you should not attempt to repair . Only if you can prove that you are a competent person

yas
October 2008

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