ferroli modena 102 help please:)

[philski84]

Hi all,

just found this site and it seems great help to many people.

i have a new built house (2 years old) with this boiler installed.

about 4 months ago my friend had to change his pcb board??

(the fitter that looked at his boiler noticed that the plug socket should have a 3 amp fuse?? and it had a 13amp fuse)

i have changed mine to a 3amp fuse.

this week for the first time, my hot water has been becoming intermittent while im having a shower?? one second boiling hot the next freezing cold?

and the boiler is making more clicking noise as i guess the boiler keeps trying to kick in ( im far from an expert so please reply in laymans terms

is there any test i can do or try anything before i call someone out?

Thanks Phil

 

[Rob]

Not too sure about recent Ferollis but the older modenas are known for faulty thermistor problems. These are the little temp. sensors.

 

[ollski]

Not too sure about recent Ferollis but the older modenas are known for faulty thermistor problems. These are the little temp. sensors.

same on the modenas, dunno how technical you are but you could swap the thermisters over to confirm fault as it will switch to heating.

 

[bengasman]

does the water go cold or does it go up and down?

 

[gasanstuff]

could be low gas pressure at boiler, you would need to get it checked.

may just be low pressure coming in and needs governor adjustment.
combined with US gas pipe then the boiler will cut out in DHW mode

 

[philski84]

Thanks for the help and a corgi engineer has just left and these are what has been done.

changed the thermistas (temp probes)

changed pcb circuit board

blown out the venturee

changed the high limit stat (top left)

checked gas inlet point which was 20.5mbar when boiler off which went to 18.5mbar when boiler fired up. ( in book it says minimum of 20mbar but engineer said anything above 18 was fine?

after all this we still had the same problem!!!!!!!!!

if on hot water or central heating the boiler runs then cuts out without warning ( with fan and pump still running) and instantly starts back up, this can happen every 5 seconds, so its (on off on off on off and you can hear the ignition click click click every 5 seconds.


after all this he changed the air pressure switch, which seems to have helped and when running hot water the system does not cut out but it does on central heating??

im now leaving the heating off for a few hours and restarting to see how the system works??


is there anything anyone can pick up from what i have explained what else could go wrong for this to happen and could the air pressure switch have cause this fault?

Thanks Phil

 

[numpty1]

it was not the pcb/aps/high limit stat get him to check the flue and remove restrictor if fitted.depending on how good he is, check the fan and clean/replace both parts of the venturi and remove dust etc from the fan blades.

 

[Gasguru]

He's changed all the usual parts these boilers require at the age they are now and that would normally sort the problem.

The venturi and pitot tube are made out of plastic and with the heat they go brittle and fail. You could ask him if they were both intact after cleaning.

Did the water pressure switch get tested?

Did the sense electrode position get checked?

Is the correct flue restrictor ring fitted?

Was the new board setup correctly. I've had problems with the latest boards getting the ignition pressures correct.

Otherwise perhaps it's a wiring loom fault or intermittant fault on the fan.

 

[bengasman]

He's changed all the usual parts these boilers require at the age they are now and that would normally sort the problem.

At TWO years old???

The numpty that came around had obviously not a clue what he was doing.
Combi dhw going from hot to cold and back, and it does not seem to be a quality installation; 2nd hex would be the first thing I checked. Apparently it has not even been looked at.

 

[Gasguru]

The Modena doesn't have a 2nd h.ex it's got a bi-thermal heat exchanger.

Thermisters and pcbs can certainly play up within two years.

Venturis and pitots on these are another weak point.

 

[bengasman]

The Modena doesn't have a 2nd h.ex it's got a bi-thermal heat exchanger.

ah, did not remember, if it ain't there, it aint't broke

2 years normal for a pcb to fail. mmmmmmh, certain poxi and a watchdog episode come to mind.

i do remember that fan and venturi problems can have funny effects on these.

 

[JonB]

Phil
Ive had a Modena 102 for 8 years now, only probs were a dry joint on PCB in the 2nd year & a pair of thermistors at about 5 years.
Very pleased with it.

 

[philski84]

Hi Guys thanks for all the comments and help but 2 months later im still no further forward!!!!!!!!!1

arrrggggghhhhhhhhh.

i have uploaded a video of what the problem is onto youtube

http://www.youtube.com/watch?v=S9ey17o21E4

if any of you kind people could take a look at it and comment?

would wind conditions outside casue somthing like this to happen?

Cheers Phil

 

[weareleeds]

Just watched video & at no time did the dhw diode come on so it may be dhw flow switch not operating (i assume you had the hot tap running)

 

[ollski]

I'd be going fan presuming that was tyring to fire on ch.