Worcester Heatslave 20/25 no ignition

[Avocet]

Hi all, Our boiler packed up yesterday. Timer comes on, runs for a few seconds and then lockout. As far as I can tell, there's no attempt at ignition. I can hear the click from the controller after the fan has been running for a few seconds (which I assume is the signal to the ignition module to create a spark), but no attempt at ignition and a few seconds after that, it locks out. Resetting the lockout button just results in the same sequence.

I had a peek inside and I can see that one of the high tension wires has been chafing on the bottom of the burner unit. The insulation is worn through to the conductor. I've bent it out of the way and dobbed a blob of silicone over the chafed bit, but still no ignition.

Pending the arrival of a new lead, is there any way I can test the ignition module? (I don't know if the short will have blown-up the module or caused any other damage).

 

[Terrywookfit]

Remove control box cover and put a link in.
Is oil being released.

 

[oilboffin]

Have a look in the blast tube if it's wet you've got fuel if not could be solenoid coil you could run the burner out in the air for a few secs you'd see sparks straight away if so the coil.Bob

 

[Avocet]

Thanks gents. Yes, there's definitely fuel. The tip of the burner is wet and smells of Kerosene. If I crack open the bleed screw in the few seconds between the pump starting and lockout occurring, I get a good squirt of oil out of it. @ Terry, when you say "remove the control box cover and put a link in", where should I put the link? Do you mean a wire between two terminals in the control box? If so, which ones? @ Bob, when you say run it in air, there's a blue wire going to a multiplug under the programmer for the boiler. It seems to have about half a dozen connectors. It's not long enough to let me put the burner unit outside though. Am I in danger of inventing a flame thrower in Mrs. Avocet's utility room?! (...only, I'm in enough trouble already for the house being cold and not having any hot water...)!

 

[Terrywookfit]

Which control box and burner is fitted.

 

[oilhead]

Disconnect the solenoid coil lead and you can look at the open burner for a spark. It won't light, just run to lockout.

 

[Avocet]

Disconnect the solenoid coil lead and you can look at the open burner for a spark. It won't light, just run to lockout.

Thanks! Tried that, and yes, there's no spark. Tried it again with the solenoid plugged back in and I get a nice mist of oil spray, but still no spark. The electrode gap was a mile away from what the installation instructions specify (about 5mm gap and about 12mm below the tip of the injector, whereas the installation instructions specify a 3-3.5mm gap and 1mm below he tip of the injector)! However, re-setting those has made no difference. I guess I'm now looking at either:

The ignition module itself,
the high tension wire(s),
the contacts in the controller,
the electrodes themselves.

Is there anything else I might have overlooked?

 

[Avocet]

Oh, I don't know if it's significant, but putting a meter on the plug that goes into the ignition module from the controller, it shows 230 Volts across the pins up until lockout. There's continuity from each of the high tension cable ends to the tip of its corresponding electrode, so I'm guessing that's the ignition module then?

 

[oilboffin]

Trannys gone.Bob

 

[boilerdoktor]

Probs control box and transformer

 

[Avocet]

A big "thank you" to you all! Replacement ignition module finally arrived today and everything now working as it should!