Problems with my Ferroli Mondena E Boiler

[WoodButcher7]

Hello, i wonder if someone can help me,.. my boiler is giving me problems. At first, every now and agein my hot water would stop working but only temporarily, i'd work fine next time i came to use it,.. this gradually got worse untill it stopped working completely,.. i got and engineer round who said it was the fan, so he replaced it, and the boiler worked fine for a couple of days then stopped working agein, he came round agein and swapped the digital timer for a mechanical timer, agein it worked fine for a couple of days and stopped agein. now i have no hot water or central heating although i can still hear the water pump working, it just does'nt seem to attempt to ignite, the radiator light comes on but the flame light does'nt. i'm pulling my hair out as i really cant afford a new boiler. please can someone shed some light!

many thanks in advance, Aaron.

 

[Andygasman2010]

It'll probably be one of the two thermistors. They're a few quid each, change them both unless you're handy with a multimeter.

Are there any flashing lights on the front of the boiler when it's playing-up?

 

[WoodButcher7]

Thanks for the quick responce and i'll be changing them tomorrow,.. no, no lights flashing just the radiator light comes on, or if i turn on a hot tap the hot water light will come on as it usually would, just no flame light and no ignition.

Thanks, Aaron.

 

[bellairaphon]

can u hear the fan?

Nath

 

[WoodButcher7]

no the fan doesn't come on at all, at first the engineer thought that might have been the problem and replaced it with a new one, that seemed to fix the problem for a short while but stopped working agein a few days later

Cheers, Aaron.

 

[bellairaphon]

on that id check low pressure switch as andy says thermistors ( just unclip and fit the new ones before taking them out and best to swap both. then id be going to pcb.

Nath

 

[WoodButcher7]

thats great, thanks for the info guys i'll give that a go, also i'd just like to ask, while i've been tinkering with the boiler i've left the casing off the front of the boiler for days at a time and after reading up on various sites i'm under the impression that this is a big NO NO, could that be partly to blame for it not working properly or is it just because it may leak gasses?

Cheers, Aaron.

 

[kevindgas]

depending on which cover you have left off!! if it is the white decor cover then no problem if it is the internal silver one then you have a problem.

known faults

fan venturi - replace it as they are ****e
thermistors - remove and clean with a nylon scourer then refit
you can prove the thermistors by swapping the wires round
flow switch and hot water tube through H/E get scale build up, can be descaled easily so long as the tube isn't completely blocked
PCB - MF003 boards are ok but the 01 & 02 versions were a mare replace with the 03 board
Air pressure switch - rarely faulty
Pressure switch - if faulty the bar light will flash even though the pressure guage reads correctly