Worcester Junior 24i Fan fault

[MK Heating]

Went to one of these today. Sequence went: Demand > Pump > Dead, light flashing slow. Getting 240v at the fan during this sequence. Went off to get a fan. Came back, fitted it. Now I get: Demand > Pump > Fan... No ignition. Took the + pipe off the fan and blew into it. APS clicks and it fires great. Is this indicative of a faulty APS? Ive ordered one in for the morning, Ive just got a bad gut feeling that this one is going to be an arkward one. Ive had a lot of breakdowns go well the last few weeks, one is going to make an idiot of me soon. When the boiler is turned on, the fan is running constantly. Im not getting an APS fault at all. fan just runs and runs.

 

[SafeGasInstall]

It could be aps and a PCB ! Remembering from reading here it was the PCB on few occasions ! Have a look on the other threads for same boiler with same fault

 

[MK Heating]

Thanks mate. Im going to stump up for the APS. If its the PCB Im going to have to give the customer the bad news. The fan was defiantly broken in the first place as it was completely dead with 240v before I got there. Just hate having to explain further things need changing. Customers these days are expecting 100% fix rate first time rrr:

 

[diamondgas]

Take a fan venturi with you too MK... I think they're the plastic one's that like to shrivel up

EDIT.... Scratch that they come with the new fan!!! Check the pressure diff across the venturi though make sure you're getting a couple of mbar! Not sure what you should expect but it can sometimes be found on the aps

 

[Ermintrude]

Just ripped one off wall if u want pcb?

 

[MK Heating]

Thanks for the offer. I told the customer whats going on. He has it screwed on so he knew what I was on about. for future reference this is what problem I had and what sorted it. Would appear whats happened is the PCB has failed causing the fan to have no OFF position. As soon as 240v was at the boiler the fan was running full speed. Upon CH demand the fan would slow. End CH demand and the fan would run for 35 secs as per the overrun sequence, but instead of knocking off after 35 secs it went back to full speed. Can only assume this fault causing the fan to run constant burned the fan out too. New fan, PCB and APS fitted all sorted. Didn't need the APS in the end but I had it so I fitted it. Nasty fault.

 

[diamondgas]

Nasty fault yeh but some satisfaction in geting it sorted eh?

 

[SafeGasInstall]

Very likely the aps has damaged PCB and fun

 

[MK Heating]

Nasty fault yeh but some satisfaction in geting it sorted eh?

Huge relief when it fired up lol

 

[diamondgas]

Huge relief when it fired up lol

That feeling never goes away MK ... I'm 35yrs down the line and still sigh relief when it fires up on some occasions...! I still get it wrong, just happens to be much much rarerer these days