Worcester Bosch Heatslave 15/19 Intermittent Lockout

[oilman]

The pump will be ok, but the coupling is no longer, so you need a new one, and you need a new rotor for the motor. That is unfortunate as it will mean buying a motor complete, unless you know of some supposedly faulty motors from which you can salvage a rotor.

Yours is the B9 burner here. Parts available here amongst others.

 

[stevecook]

Thanks Oilman for coming back so quickly. I suspected as much. I don't know of any secondhand rotors so will see if local spares supplier has a motor in stock. It looks like it just unbolts via 2 allen head bolts on flange. Is it as simple as that?

 

[oilman]

Yes. Then the fan needs to be removed. Check the clearance between the motor and the fan before removing it. This is critical when reassembled, and you get jammed or graunching motor if its wrong.

 

[stevecook]

Sounds critical indeed but I'm up for it. Have located motor locally so just off to get it. Will let you know later.

Steve

 

[stevecook]

Fitted new motor and reassembled. I'm pretty sure I assembled correctly especially fan/motor clearance. Initally fired but locked out after 30seconds or so. Reset twice and locked out quicker, the last time without firing although I think I heard a click like a spark before lockout. Is the problem because it needs bleeding? I know there's a bleed nipple on top of the pump but not sure how to do it if I need to.

 

[OilLecky]

Well done Steve! If you've disconnected the fuel lines to the pump or checked it's internal filter (hopefully you did both) then you'll need to bleed the pump. Make sure that you have turned the oil back on after refitting the pump. Put a container under the pump, then, using an Allen key, loosen the little plug with a "P" written next to it on the oil pump. This is where we fit a pressure gauge. DO NOT ADJUST the Allen screw that has a graduating curve around it. This is the oil pressure adjustment screw. Run the oil until the bubble stop. (If you are really brave aand have an assitant you can finish the process by getting them to swith the boiler on while you have the plug cracked open. Make sure that you have a rag covering it though!!!!
I'm fairly sure that you can download the manual from the Wocester Bosch website for your boiler / burner.

 

[stevecook]

Thanks OilLecky for the vote of confidence. I didn't however disconnect the oil feed nor did I check the filter cartridge when I removed pump, only disconnected the nozzle pipe at the pump end. It sounds like I should have checked the filter cartridge anyway as good practice. Just now I've done the brave thing and cracked the P screw open whilst pressing reset. It bubbles like bleeding a radiator but instead of getting more of a spurt or steady drip the oil dries up and nothing comes out - then lockout. Tried it 3 times with same result. I could loosen the P screw quite a bit but still nothing came. By the way I didn't turn off the oil feed valve at all during my efforts - perhaps I should have. What do you think?

 

[oilman]

The bleed nipple on the top of the pump is easy if you have a piece of tube that is the right size to push on the top, then put the end in a pot and open the nipple. I don't have a piece of tube, so I shut off the oil line and remove the pump inlet, stick that in a pot and open the oil line tap.

 

[stevecook]

Stop Press- I wondered after I'd written it that perhaps I might have turned the oil off inadvertently - I'd certainly played with the thumbwheel intending to stop the oil supply but thought better of it and left it as it was. Anway fiddled with the valve (I really don't think I understand how this thumbwheel operates. I'm looking at it like a stopcock but maybe that's not how it actually works ) and voila! The P screw dripped and the boiler fired
I can't thank you enough OilLecky and you Oilman and all the guys who took the trouble to think about my problem. Absolutely priceless. Take care if we don't talk again but if we do at least I'll be a little less green.

Steve

 

[OilLecky]

Well done Steve. Yes the rotating oil valves can be confusing both the Atkins combined valve / filter / sight gauge, as fitted to tanks and the little manual "fire valves" operate the same way as a water tap. i.e. Clock-wise, from above, to close. They feel odd because the centre pin seem to be going the wrong way. If you are opening / closing the little fire valve that is mounted on the oil pipe be careful and only turn it gently, as any force will break the solder plug and it will snap closed. ( This solder melts if there is a fire nearby.)