GLOW-WORM 30CXi problem please help.

[wazza99]

My problem.

Boiler stopped working one morning.

Our local gas engineer attended and found the condensent drain had blocked causing a water leak inside the boiler and consequently the fuse had blown on the main PCB.
So drain cleared, water cleared, fuse replaced. Boiler fully serviced at same time.
Problem is now although the central heating works wonderfully if we turn on the hot tap within seconds the boiler shuts down, red light flashs and F17 shows as error on display. The boiler then restes and does the same until the tap is turned off. We are aware the F17 is voltage less than 170 but this seems very odd as the voltage at the input is always 240 (via multimeter) .
Engineer has changed the Overheat Thermostat and both Heating thermistors without any luck.

Please could you advise ? we are currently thinking possibly the flow sensor ?

 

[breezer]

pcb corroded?

 

[urbanspaceman]

plate heat exchanger full of debris...needs to be removed and flushed or replaced

 

[wazza99]

I don't think it could be PCB as this sits vertically at front of boiler and didn't get any water on it, though why fuse blew on it ?? but thx

 

[Agile]

Fuses blow when the rated current is exceeded in order to protect the circuit during a fault condition.

If the fuse blew then there was a serious fault and it sounds as if water entered an electrical assembly and has damaged it.

The cause of the blown fuse needs to be found and the appropriate remedial action taken.

Tony

 

[Alfredo]

We tend to play "Dart Board Engineering" with these things. We just throw parts at it until one sticks!!

Seriously though, if the CH works OK then I'd take a bet the PCB is..PROBABLY..OK, and I tend to go along with replacing/cleaning the plate to plate as, if for no other reason, you have to eliminate it as a possible cause, and it could certainly produce the symptoms you describe.

If you clean the P to P and the fuse blows again..THEN its got to be PCB related. We do tend to find that most PCBs will survive a brief ducking as long as they are dried out properly, and as long as there is no corrosion evident on the board.

We've had a few leaks with these, but the only really embarrasing one was the flooded Cxi where the Glo Worm(heatcall) bloke found the blanking plug still in the condensate pipe on the boiler . The installer repsonsible had left by then, and it was very out of character..soo we are all but human!

Alfredo

 

[wazza99]

Thanks for replies, should say fuse has only blown the once and never since, can get a slow flow of hot water but as soon as i turn up to full or anything like full ,,,,F17 error and bolier "reboots@ !

++++++++++++++++++++++++++++++++

Oh and just thought i'd let you all know called Glow-worm to try and get an engineer out (chargeable) and they refused, said they are taking no calls from paying customers over the winter period !! pretty poor i thought,

 

[Alfredo]

I understand your feelings, but I suspect that they (and others) are a bit short of engineers. Its a mugs job as you do loads of travel, get a limited time to fix boilers, and you stand no chance of diagnosing intermittent faults without multiple visits..whereas everyone expects miracles as you arrive in the company van...No I have never done this sort of job, but I'm not unduly attracted to one as I've seen the turnover.

Intrestingly Worcester Bosch told me that their engineers vans are restocked every night outside the houses of the engineers in the middle of the night so the engineer has full stock every morning. Not sure i'd want the restocking job! I like my sleep (he says having been on 24 hour callout duty all week..ten call outs on saturday...all fixed!!)

Alfredo

 

[nickso]

worcester engineers have an average first time repair of 98%.

they do however have the luxury of a van with every part in it and they dont work on the system at all...... only the boiler.

the van restocking thing is not uncommon... isused to get that in my last profession.

glowworm are awful for sending out engineers. i once heard of a glowworm manager going to a repair. when he realised there was actually a fault and it wasnt just the customer taking the **** he said he wasnt registered walked out

 

[desperateoftatling]

Oh and just thought i'd let you all know called Glow-worm to try and get an engineer out (chargeable) and they refused, said they are taking no calls from paying customers over the winter period !! pretty poor i thought,

Did you ever manage to resolve your problem, as I am experiencing exactly the same thing on a 38 CXI. Would really appreciate your input !

 

[andsam]

Fan transformer PCB faulty. (thats if its the older type and it is mounted under the fan)

 

[wazza99]

Turned out to be a faulty PCB, cost me around £280 with callouts to get it fixed

 

[wazza99]

Time to revive this boiler thread ! well its lasted 12 months now more problems

Firstly the hot water temp has dropped, everything else works fine just that the hot water isn't very hot (ie you can hold your hand under it) im thinking this time it probably is the heat exchanger full of crud. I looked back on the install sheet on the engineer has ticked the box to say he flushed in accordance with instructions but to be honest i doubt it. We have since parted company !

Secondly i have noticed twice now the earth lead at the point where it joins the "spark plug" ie the spade connecter must get very hot because it seems to be melted and corroded ?? have replaced it but why should thos occur ? Unrelated to hot water i know but any advice greatfully received.

Main thing is is it really feasible for me to remove the heat exchanger and clean ? and does anyone have any "clear" intructions how to do so. Or do i need to get my cheque book out again !
Thanks

 

[gas_man_gaz]

on these boilers the manufacturers advise the case seal be replaced (been upgraded to a graphite seal) that or the sight glass seal would cause the scorching to the earth lead, both come in the pack anyway..

as for the poor hot water could be loads of things - best to get a engineer out as alot of the things ya wouldn't be able to check.. may be that the water coming in is cooler? could check to make sure ya diverter isn't passing to heating (wen sys cold run ya hw tap, make sure the boiler fires up and feel the ch pipes under the boiler to make sure they dont get hot)

and bg do a fixed price repair of £156 (parts and labour) and they might change ya case seal while they are there (free of charge) i no i would! £156 is for 1fault only tho

 

[ChrisR]

Main thing is is it really feasible for me to remove the heat exchanger and clean ? and does anyone have any "clear" intructions how to do so.

Well, the instructions work, but you have to move gas pipery so it isn't a diy job.