Boiler ok for HW but pilot goes out when CH comes on

[Rustywhiskers]

hi our dinosaur boiler which when it works is great is having a senior moment! (1975 Thorn)

the HW has been on for an hour twice a day all summer - switched the heating on this week & it worked..... but at some point during the 5 hours its on for in the evening the pilot light went out. So no heating or HW the next morning.

re-lit it - same thing again.

have had one instance of it staying lit all night & providing HW & CH next morning & then going out again.

Any ideas why each time the heating comes on the pilot light goes out about an hour in to the cycle?

Any help appreciated

RW

 

[SimonJohns]

Have you had it serviced recently

What was he last part changed

I think you may need an engineer to attend. Be sure to tell them you have issues with the pilot so they bring a part that is usually the issue with
Them

Don't worry, it's a very cheap part

 

[Rustywhiskers]

thanks - as its soooo basic a boiler there is nothing to service on it apart from twice yearly clean out - have replaced the thermo coupling a few times over the years & my husband is currently doing that again now so fingers crossed that's all it is - seems unlikely tho as it works for the hw & cuts out for the heating

 

[Rustywhiskers]

might be speaking too soon but changed the thermocoupling & all is hot hot hot......