105he fan flue fault...but how???

[danny boy]

Hi all

Wonder if anyone can help me, i have spent the last couple of hours wrestling with a 105he...here is the tale. I got asked to go look at the boiler and when i got there the boiler standby light was on, when i called for heat the correct calling light came on then after 10 secs a fault light came on saying pump problem(when calling the lights came on bot nothing operated in the boiler). Tested the pump whiched was goosed so changed that, called for heat, fan started, pump ran but no ignition. Tested the fan and had 240v when running and correct resistance when off so i hurridly came to the conclusion its the APS. Changed it, still no joy. Took the fan apart, and cleaned out the venturi and air blasted the main flue, still no joy. I then took the black tube (Black and clear tubes connecting APS to fan) and boiler fired up...hey presto! Re connected the black tube and back to square one.

Got me a bit confused, anyone had this before???

 

[diamondgas]

Not on this boiler but I'd be checking the venturi to see what pressure difference is produced ... 'u' gauge connected to both pipes yeh?

 

[desrob]

simple, but you never know make sure pipes are in correct order

 

[Billy Bob Bob]

check the flue,did you fit a genuine aps?

 

[danny boy]

Flue was totaly clear and aps was like for like,,what should the differnce be steve?

 

[Billy Bob Bob]

tubes and wires the right way round?

 

[diamondgas]

If only I knew Danny Boy 🙂 It might be printed on the side of the aps though ... I'd be looking for something over 1mbar! If I was at home I could quickly find out but not there 🙂 Maybe someone here knows, or knows where to find out?

 

[Billy Bob Bob]

If only I knew Danny Boy 🙂 It might be printed on the side of the aps though ... I'd be looking for something over 1mbar! If I was at home I could quickly find out but not there 🙂 Maybe someone here knows, or knows where to find out?

i only have the adjustable type in stock at the mo so thats no help

 

[Billy Bob Bob]

one thing worth checking follow the fan aps loom to the pcb i have had the pins come out on the jackplug at the pcb

 

[danny boy]

Cheers lads i'll have a look today aand keep you updated

 

[SafeGasInstall]

swap the aps , had to not working from parts centre last week

 

[diamondgas]

danny boy .... The baxi aps is 1.2-6mbar .... the 105HE I have here at home does 4.5mbar hope that helps🙂