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Andrew Smith
Andrew Smith, Engineer
Category: UK Plumbing
Satisfied Customers: 3609
Experience:  Domestic Gas, Commercial Gas, LPG, Unvented Hot Water, Part P Electrical, Commercial Catering
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Worcester Bosch 25Si boiler - after the high winds, the boiler

Customer Question

Worcester Bosch 25Si boiler - after the high winds, the boiler has tripped out - i have a slow flashing blue light and red flashing reset light. I have tried many times with the reset button and total power off and on again. When the boiler powers up it goes thro what i assume is its 10 second start up routine, the drops out the the flashing fault?
Has the wind down my flue damaged something?
Submitted: 5 years ago.
Category: UK Plumbing
Expert:  Andrew Smith replied 5 years ago.
Hi my name is XXXXX XXXXX lets see if we can get you sorted in the shortest possible time. Can you hear the fan running?
Customer: replied 5 years ago.
the fan runs until the whole thing trips out again.
there was some water in the cabinet which probably came from the rain driven into the flue by the winds. I mopped this up and put a fan heater on the boiler for 2 hours to dry it out. After this, the heating ran ok for an hour until the wife ran the hot water to wash up. When she turned the tap off, the boiler tripped out again and i am back where i started. I am wondering if it is something to do with the ignition system - when i reset, it tries to light up but fails and locks me out again?
Expert:  Andrew Smith replied 5 years ago.
It will lock out if it fails to light. If you take the front cover off and clean all the electrodes with Scotchbrite or something similar (there may be 3) and then try again. Let me know what happens.
Customer: replied 5 years ago.
how do i get to the electrodes - is there a diagram somewhere for me to download?
Expert:  Andrew Smith replied 5 years ago.

If you take the cover off, then the four screws holding the combustion chamber front on. The electrodes are inside there. You can download the manual from here; http://www.worcester-bosch.co.uk/homeowner/literature/discontinued-boiler-literature/discontinued-gas-boiler-literature/25si-old-model-october-2001-march-2002-literature

 

Customer: replied 5 years ago.
Andrew - thanks for getting back to me. Wanted to get home and have a look before responding. Seems i am a collosal pillock - my boiler is in fact a 30si, installed in Jan 2006. We had no trouble yesterday whilst it was running but when i got home tonight, it had tripped out again. Is the 30si ignition system the same as the 25si? Are the electrodes easy enough to get out and clean? If so, how do i get them out?
Many thanks.
Expert:  Andrew Smith replied 5 years ago.
The 25si and the 30si are the same. Once you have the covers off you may just be able to clean all the electrodes in place with a light emery paper or similar.
Andrew Smith, Engineer
Category: UK Plumbing
Satisfied Customers: 3609
Experience: Domestic Gas, Commercial Gas, LPG, Unvented Hot Water, Part P Electrical, Commercial Catering
Andrew Smith and other UK Plumbing Specialists are ready to help you
Customer: replied 5 years ago.
Andrew,
the boiler is working ok now so i am not going to start taking it apart. If it happens again, i have an idea what to do so thank you for your help.
Darren
Expert:  Andrew Smith replied 5 years ago.
Great news
Customer: replied 5 years ago.
bag o craps gone off again this morning - do the electrodes come out for cleaning & if so, how?
Do they work like spark plugs?
or is the dirty connection going to be on the top of the electrode like a spark plug? WD40?
Expert:  Andrew Smith replied 5 years ago.
They are just electrodes connected to the spark generator. As soon as you take the front panel of to the combustion chamber you will see them in front of you. A slight clean with some emery paper.
Customer: replied 5 years ago.
sorry if i'm being thick - the combustion chamber appears to be a cylinder - there is a black plastic access panel at the bottom - other than that, i cant see how to get into the chamber without pulling the whole thing out and then taking the top off? I can see the three electrodes at the top but the diagram in the document you pointed me at says i have to take off other things before lifting out the electrode panel.
Added to this, i have a pool of water in the bottom of the cabinet again....it didnt rain last night so where might the water be coming from? Is there a leak which might be causing the boiler to trip off and fail to ignite? The pressure in the central heating had dropped below 1mb as the outside temperature dropped to frosty last night.
Expert:  Andrew Smith replied 5 years ago.
Is it the HE model?
Customer: replied 5 years ago.
user guide says Greenstar 25Si/30Si, installed 2006
Expert:  Andrew Smith replied 5 years ago.
Do you have a white overflow pipe coming from under the boiler to outside?
Customer: replied 5 years ago.
yes - and it is clear - i heard water trickling thro over the weekend.

when we had hard frosts in December, i diconnected it and dropped the water into a bucket while the white overflow was frozen up
Expert:  Andrew Smith replied 5 years ago.

Ok, so it is the HE model, that is different. The heat exchanger is circular, the ignition electrode is screwed to the front (with a wire and earth wire attached to it) it should be attached with a couple of screws

Customer: replied 5 years ago.
is it at the bottom, near the black plastic access panel?


Customer: replied 5 years ago.
Relist: Incomplete answer.
was advised on the wrong boiler then when i asked for more info, i think he just gave up...with my £17 in his pocket
Customer: replied 5 years ago.
still waiting for an answer?
my problem has not gone away................
Expert:  Rick Ridley replied 5 years ago.
Hi I am Rick, UK Plumber, and I specialize on Boiler problems, I have just gone through the posts here, I do not think the high winds will have effected your boiler, I will check through the fault finding and come back soon, Rick
Expert:  Rick Ridley replied 5 years ago.
can you tell me the flash sequence of the blue light is it long on and short off,, or long off and short on, Rick
Customer: replied 5 years ago.
long on, short off + blinking red reset button. Got another small pool in the cabinet. When it was running earlier, i noticed alot of condensation on the inside of the cover and steam coming from around where the flue outlet. When i checked the mounting, all three screws were not tight. I suspect this steam is the source of the condensation and in turn / over a few hours / days the pooling of the water in the cabinet.
Is the damp caused by this causing the boiler to trip off?
Expert:  Rick Ridley replied 5 years ago.
OK this sequence is flue and or heat exchanger over heat, and from what you are saying about the condensation and water in the cabinet, you have a gasket blown and this will need to be addressed urgently it is unsafe to continue to use the boiler if part of the broken gasket has gone inside the heat chamber it can do serious damage, you realy need a profesional to look at this as when it is reasembled the gas/air mixture will need to be tested and adjusted and this can only be done with professional equipment, regards Rick
Customer: replied 5 years ago.
Rick, many thanks - i'll make a few calls tomorrow and let you know how we get on.
Expert:  Rick Ridley replied 5 years ago.
no problem, but please understand the boiler is leaking flue gasses which are potentialy very dangerous, Rick

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