Hot water only for 20 seconds

[yellowfish]

Hi,

Have a Biasi Prisma S 28SE boiler.

Have set the boiler to the winter setting (which allows it to only come on when the hot tap is turned), working fine for the last two months - But now when I turn on the hot tap sometimes the pilot light comes on for 20 seconds and turns off, other times it never comes on. So I get no hot water.

I set the boiler back to winter, again it continues as above.

Any ideas?

Thanks for your help

 

[kevplumb]

diaphram in the diverter
bottom right near the pump
see if the pin is lifting when running hot tap

 

[yellowfish]

thanks for the quick response, could you just claify where and what I'm looking for

Thanks!

 

[kevplumb]

have you got the service manual

 

[yellowfish]

Just downloaded it off the web - Thanks

 

[kevplumb]

section 8:1 page 15
if you have got the service manual

 

[yellowfish]

Thanks - Don't suppose you have a user manual?

Also when the bolier is switched off from the mains, should the nobs for the winter/summer water/central heating being on a particular setting?

Thanks for all your help

 

[kevplumb]

e mail me
adress in profile
will send it

 

[yellowfish]

If the Pins not lifting then what?

Thanks -

 

[kevplumb]

diaphram (membrane) has split , streched . perished

 

[yellowfish]

Thanks for all your help yesterday, when I got home i tried the boiler and it started working!! Totally bonkers,