Potterton Suprima 40

[lfarndon]

Can you help?
I have a Suprima 40 which had the PCB changed in the summer of 2006 due to the usual dry joint problem. The heating engineer fitted a new style board. Today I walked in from work to find the radiators cold and a red flashing light on the boiler. I pressed the reset button and listened to the fan start up and the ignition spark approx 10 times but it did not light, the boiler retried 4 more times to light but didn't. Then went to red flashing light mode
I tried the APS and it was ok with a suck test and then listened to it as the fan worked - it's ok.
I then fitted the old board (which the engineer left with me) to see if it would light up but it had exactly the same fault - fan running, good spark but no burn.
I suspect the valve but can anyone give me any other simple checks to make before calling a heating engineer out?
Any help appreciated - thanks
LF

 

[corgiman]

if you have a multimeter check the ohms across the first and last pins of the gas valve.

turn the sparks off first

 

[lfarndon]

I have a meter at work, will try tomorrow.
What should I expect to get - continuity and/or what value?

 

[corgiman]

if its Open circuit its dead

they usually show 4 kohms when ok ( im sure someone will put me right if i is wrong they often do )

 

[lfarndon]

Thanks Corgiman

How much to replace the valve (T&M) as I'm not corgi registered?

 

[kevplumb]

Thanks Corgiman

How much to replace the valve (T&M) as I'm not corgi registered?

don't ask im ees a bandit

i know i taught im

 

[corgiman]

I think the valve is about 140 knicker plus vat and an hour to fit

I could and probably am about the price of the valve but i am not far out

 

[The_Wilderbeast]

I have one of these and had a similar problem a month or two back. I drained down the system to replace a rad and it airlocked on restart. I ran the pump with the gas off for 30 mins and then on restarting with the gas on it locked out, I must have reset the thing 50 times that day and was resigned to calling a plumber out (figured the PCB was probably screwed), the following morning it started fine and hasn't been a problem since. Around the time of the problem I checked out several forums and they all seem to have this down as a recurring problem. I haven't got a magic cure that got mine going, just thought it might be of interest to you.

 

[baxpoti]

Do you always walk home from work?
or was it just today?

 

[lfarndon]

could anything else cause this fault?
What about water supply, will the boiler still spark if the water pressure has dropped?? I'm also concerned about the flow sensor.........

 

[lfarndon]

I have one of these and had a similar problem a month or two back. I drained down the system to replace a rad and it airlocked on restart. I ran the pump with the gas off for 30 mins and then on restarting with the gas on it locked out, I must have reset the thing 50 times that day and was resigned to calling a plumber out (figured the PCB was probably screwed), the following morning it started fine and hasn't been a problem since. Around the time of the problem I checked out several forums and they all seem to have this down as a recurring problem. I haven't got a magic cure that got mine going, just thought it might be of interest to you.

I turned the water off yesterday to fix a leaking tap, but the heating and hot water were ok last night & today until about 5:30pm today........I'm wondering now if it is to do with the water feed to the central heating.......

 

[lfarndon]

Tested the valve and it was open circuit.
Called a heating engineer and told him it was the valve and he said it could be the pcb as well (one failure could cause failure on other).
Measured voltage coming from board and it was fine (over 200v).
Heating engineer replaced the valve and I now have a fully working boiler.
Thanks for everyone's help with this.

 

[corgiman]

Thanks Corgiman

How much to replace the valve (T&M) as I'm not corgi registered?

don't ask im ees a bandit

i know i taught im

hopalong cassidy and the bacon sarnie kid as we were once known


Glad to hear you sorted it, and I will allow myself a little YAY for getting it right so here you go

YAY

 

[Agile]

And just for the record what did it cost for the engineer to replace the gas valve?