Worcester Heatslave 15/19 OIL - Lockout issues

17 Oct 2012
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United Kingdom
We have a Worcester Heatslave 15/19 which has an issue with the Lockout frequently happening.

By Lockout i mean the red \ amber lamp that lights on the burner control box.

This issues seems to raise it head at the same time every year when we have the Boiler doing the CH and the Hot Water both at the same time.

Throughout the rest of the year when it is only heating water we don't have this issue.

The reset button which is lite can be pressed and it will fire the boiler up and start heating the water again, but having a young family all getting ready in the morning is a push as it is even more so when you get up and have run down stairs and press the button and wait for hot water.

The boiler was serviced within the last 12 months, but this issue continues, any suggestions guys? Because of the nature of the fault when it is doing both is it over heating somehow and shuts down?

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A few suggestions, but none of them conclusive.....
1) The solenoid coil on top of the oil pump. Very prone to failure when it gets hot, and gives no warning!
2) The motor start capacitor, which tells the burner motor which way to spin
3) Are all of the filter(s) in the oil line clean?
John :)
All of the things that John has suggested are related to burner lockout.

If it only occurs in certain use situation that would indicate it an overheating ( if that lockout is also activated by an overheat ).

Its difficult to guess why there would be an overheat situation as properly configured there would be more heating water flow through the boiler.

Have you not discussed the problem when its been serviced?

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Thanks for all the prompt replies guys.

It was discussed last service and I think from memory the divertor valve may have been suggested and checked \ replaced. I need to dig the previousl invoice out to be sure.

The solenoid coil on top of the oil pump - sorry do you have a schematic which shows this or a part number?

I have a spare pump so will the spare pump have this and I can simply take it off the new pump and put it on the old pump?

Thanks again
You can use the old coil (presumably its a good one) from the old pump onto the new....I guess you'll have a B9B burner and a BFP41L3 pump.
Its held on with an allen nut, and just pull the electrical connector out.
I think the part number is Danfoss 071N0010 and they cost between £25 and £30.
John :)

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