Worcester Heatslave burner motor won't start when warm

[Nixt]

Last post was not aimed at you Oilman

 

[oilman]

I understand that, but OP seems quite a reasonable guy, informs of all attempts to find more details, and combies can be a pig, even when you think you know about them.

PS I didn't think my last post was appropriate, so I've changed it. Hope it didn't offend.

 

[Nixt]

No offence taken Oilman - If heatbank fires for 30mins it should shut down boiler as its probably satisfied and won't call again until either static heat loss or dhw run. If dhw then not hot enough at outlet their could be transfer problem at plate. However if heat bank not reaching temp then flow pipe from heat bank to plate HE will be cool, which may indicate other fault such as you mentioned - store stat, diverter etc.

 

[oilman]

Have you opened the bleed nipple on the boiler? Not the auto air valve or the nipples on the pipes, but the one on the boiler. Air in the boiler causes interesting problems with the stats.

 

[SomewhereInSiberia]

Thanks for your suggestions Oilman.

Your (and Wilhelm's) thoughts on the controller and a bit of trial and error on my part seemed to work in the end. I swapped the control box (TF830.2) with that on an identical boiler (my parents') and the full range of problems went over with it. My boiler now working fine with the replacement fitted and the exact same symptoms are demonstrated on the second boiler. I've ordered a new box for my boiler (not really fair keep their's) and will fit later today.

Thanks to everybody that contributed, I've learned a lot and really appreciate the time that you've taken to help.

 

[oilman]

Thanks for the update. Make sure you check the expansion vessel regularly.

 

[SomewhereInSiberia]

Thanks Oilman, I will keep my eye on it.

 

[jetwashking]

hi, i just had this issue... i started by servicing the boiler with electrodes and fuel jet and noticed the burner was noisey. i removed the motor (unplug wire, unscrew the metal pipe from the fuel pump and remove 2 CSK allen screws from the base) and spun the fan by hand. the noise seemed to be bearings so i replaced the motor. the fault now began ! the boiler would run but then locked out and when i press the lockout reset the motor buzzed. i thought i had assembled the motor in error but not. i removed the fuel pump and turned it by hand. i noticed tight spots on rotating the Danfoss BFP fuel pump shaft so replaced the pump... my top tip is that the B9 burner unit is EOGB for worcs and if you buy the EOGB parts not Worcester parts they are half price ! i sourced my parts online from sparesgiant who let me into the EOGB secret ! http://www.sparesgiant.com/p-83510-worcester-bentone-b9-burner-danfoss-bfp41l3-87161427430.aspx