Potterton Profile 50e not sparking

[Michael29068]

Hi, I am looking at a Potterton Profile 50e on which initially the fan was cycling on start up. I changed the Pcb and this sorted the cycling problem however I cannot get it to start sparking.
I have checked air tubes and restrictors to Air Press Switch and also Air Press Switch is changing over. Door seals are ok and connections onto pcb are ok. I have also changed ignition lead and electrode, but it will not spark for me. I have also tried another Pcb.
Any suggestions anyone.

 

[Last Plumber]

Have you tried with case off ?

 

[Michael29068]

Have you tried with case off ?

I have and I have even disconnected hoses from APS and connected an external hose to APS to simulate fan running therefore changing APS state. Thanks for your reply I am baffled.

 

[Harvest Fields]

Is there power at the pcb? And if yes is there power on the A.P.S and Fan. If not check your wiring on the PCB.

 

[Michael29068]

Is there power at the pcb? And if yes is there power on the A.P.S and Fan. If not check your wiring on the PCB.

There is power to fan and Aps as Fan is running as I am activating Aps

 

[Harvest Fields]

Check all the connections on the board. If necessary go through every wire again. Is it clicking at all? Is there power at the gas valve?

 

[Michael29068]

Check all the connections on the board. If necessary go through every wire again. t isIs it clicking at all? Is there power at the gas valve?

It is not clicking at all, there is no power to pilot solenoid on gas valve

 

[Harvest Fields]

Surely if there is power to the fan and aps. I would be checking my wiring on the new board. Sounds like either APS or board. Check APS tubes are on the correct way around and pcb has been wired correctly and fuses are ok if there is any on the board.

 

[Last Plumber]

Is there 240 v between T2 and T4?
Have you replaced APS?
Have you checked overheat stat?

Here !

Page 26

 

[Michael29068]

Is there 240 v between T2 and T4?
Have you replaced APS?
Have you checked overheat stat?

Here !

Page 26

I have not checked voltage between T2 and T4.
I have replaced APS.
I have not checked overheat stat.
I will check these tommorrow. Thanks.

 

[Harvest Fields]

I have not checked voltage between T2 and T4.
I have replaced APS.
I have not checked overheat stat.
I will check these tommorrow. Thanks.

Also mate sure that the inner flue has not corroded where the terminal is.

 

[SavageW]

Pretty sure a profile wouldn’t spark without the case on even with a new APS,sometime trying to simulate enough pressure to operate the switch is not exact enough & trying to see the spark with the case on can be hard to confirm.Try disconnection the HT lead from pcb an using an insulated screw driver near by weather it’s bridging a spark to that. If you’ve got continuity through your lead then there is no reason it should not spark at pilot assembly. Could be wrong but maybe take out pilot injector an check this is not blocked

 

[Michael29068]

Pretty sure a profile wouldn’t spark without the case on even with a new APS,sometime trying to simulate enough pressure to operate the switch is not exact enough & trying to see the spark with the case on can be hard to confirm.Try disconnection the HT lead from pcb an using an insulated screw driver near by weather it’s bridging a spark to that. If you’ve got continuity through your lead then there is no reason it should not spark at pilot assembly. Could be wrong but maybe take out pilot injector an check this is not blocked

thanks for your replie





Thanks for your replies, I have not got back to this boiler yet but I have disconnected HT lead already and checked whether it is bridging a spark and it is not, as for the pilot injector being blocked I am not not getting a spark at the electrode to light the pilot even if it is clear. I seem to get the APS to change over when the fan runs.

 

[jtsplumbing]

You say that you tried another PCB ? was it a used one ? as the second board could be faulty !

 

[Last Plumber]

Pretty sure a profile wouldn’t spark without the case on even with a new APS,sometime trying to simulate enough pressure to operate the switch is not exact enough & trying to see the spark with the case on can be hard to confirm.Try disconnection the HT lead from pcb an using an insulated screw driver near by weather it’s bridging a spark to that. If you’ve got continuity through your lead then there is no reason it should not spark at pilot assembly. Could be wrong but maybe take out pilot injector an check this is not blocked

You’re right. I wasn’t thinking. It’s a positive pressure case isn’t it.

 

[Michael29068]

You’re right. I wasn’t thinking. It’s a positive pressure case isn’t it.

I have tried a new PCB and a new APS

 

[jtsplumbing]

Got to be the fan not running fast enough or you have been unlucky & new board was faulty !

 

[Michael29068]

Got to be the fan not running fast enough or you have been unlucky & new board was faulty !

I am going to try another PCB which I know has come from a working boiler and make sure that the Fan is changing over the Aps

 

[ShaunCorbs]

blow down the aps tube if you can

if it fires fan not spinning fast enough

 

[Harvest Fields]

I am going to try another PCB which I know has come from a working boiler and make sure that the Fan is changing over the Aps

Was the APS from a working boiler?

 

[Michael29068]

Was the APS from a working boiler?

I have not got back to this boiler yet, when I do I am going to try a used PCB first and maybe then a used APS which I have taken off a working boiler which I have replaced with a new high efficiency condensing boiler. I have already blown down the APS tubes.

 

[ShaunCorbs]

did it fire?

 

[Michael29068]

did it fire?

did it fire?

No, it did not even start to spark.

 

[ShaunCorbs]

No, it did not even start to spark.

so that means it didnt sense the fan was running

 

[Michael29068]

so that means it didnt sense the fan was running

I dont know as I did not Voltage on T2 and T4 connections at the time

 

[Michael29068]

I dont know as I did not Voltage on T2 and T4 connections at the time

I left out word "check" between not and voltage

 

[SavageW]

Not 100%sure but Is there a Venturi on aps tube before aps, if there is check this? You may have already by passed this by blowing down the aps if you went straight on to the positive connection on it.If so got to be slow running fan or flue.
Had ridiculously high emissions from profile before an I put it down to glue & turned out to be slow running fan, could be same in your situation but the fans got to point where it won’t even operate the APS

 

[Michael29068]

Not 100%sure but Is there a Venturi on aps tube before aps, if there is check this? You may have already by passed this by blowing down the aps if you went straight on to the positive connection on it.If so got to be slow running fan or flue

 

[Michael29068]

Not 100%sure but Is there a Venturi on aps tube before aps, if there is check this? You may have already by passed this by blowing down the aps if you went straight on to the positive connection on it.If so got to be slow running fan or flue

I have checked the Venturi and it is not blocked, have alsolconnected a tube externally to APS to activate it

 

[SavageW]

Sounds more like APS then mate,can’t remember but is it a 3 wire or 2?
*just read you’ve already tried a new one,I’m out of ideas but be interesting to know how you get on

 

[Last Plumber]

Forgive me for not reading all this again.
Have you checked the obvious like spark gap, electrode, strike point, earthing, HT lead, etc

 

[SavageW]

Forgive me for not reading all this again.
Have you checked the obvious like spark gap, electrode, strike point, earthing, HT lead, etc

Earlier on he said that he wasnot getting a spark at all,even disconnecting HT lead from pcb an bridging from the pcb to a insulated screw driver

 

[Michael29068]

Forgive me for not reading all this again.
Have you checked the obvious like spark gap, electrode, strike point, earthing, HT lead, etc

I have checked all items you detailed and even had a friend of mine take a look at it. This friend works on gas appliances only. I hope to have another look at it over the next day or so.

 

[Harvest Fields]

Think the APS is two wire but I could be wrong. I have been before

 

[Michael29068]

Think the APS is two wire but I could be wrong. I have been before

Aps is 3 wire