worcester bosch heatslave

4 Jan 2006
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United Kingdom
A mate of mine as an heatslave boiler 12/14 i think. He had recently run out of oil without realising. Since the oil tank as been refilled the boiler lockout light comes on after around 2mins of switching the boiler on. Then if you switch the boiler on soon afterwards the lockout light comes on after about 20 seconds. After leaving the boiler for a longer period of time it takes around two minutes for the lockout light to come on. Weve checked the oil line which had a lot of sediment/sludge from bottom of tank. We disconnected a pipe under the house(static caravan)and cleared any remaining debris. Weve disconnected the oil feed at the boiler and oil runs ok so we dont think it is this that is causing the problem but not sure.the boiler was running fine before it ran out of oil. Could it be a problem with the pump or anything else any suggestions would be appreciated
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As above.....one on the tank, the other screws into the pump below an allen screw - BFP41 L3 pump on these.
John :)
Yes we checked the filter on the pump which was clean and clear. There isnt one from the tank itself and when we disconnected the flexi hose from the pump oil ran freely. Cheers
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I'm surprised that there isn't a filter at the tank... :confused:
If the internal pump filter was clear (there's usually something in it)
then there's no need to suspect the nozzle filter really, although a new nozzle could be a good idea if its getting on a bit.
You may like to drain at least a 'pipeline' full of oil through, just in case there's an air lock.
John :)
Weve run quite a bit of oil through to eliminate any airlocks. When we took the filter off it looked really clear. There was like a plastic rod in the filter which wasnt central to the filter itself it was more to one side. Will try a new filter but if this doesnt work what else could it be. Thanks for your replies
The pump filter is just a cylindrical nylon gauze - if there are no splits then all should be well. So, if the oil is clean and plentiful and there are no airlocks, then we could be looking at coincidences.....
If your mate's system has a balanced flue, try running the burner with its outer box taken away - this allows the burner to draw its combustion air from inside the room.
The BFP oil pump has a solenoid coil attached to it - these switch the oil supply on electrically and they are notorious for failure.
Do you know when the system was last serviced? Its dead easy to lift out and clean the baffles on these, but to set the burner up correctly needs a pressure gauge and a flue gas analyser - this simply can't be done by eye!
If you access the nozzle, you'll see the sintered copper filter on its back end - if its really black its been there for ages. resist the temptation to take the nozzle apart, just fit a new one.
Be lucky!
John :)
Thanks for your reply, knowing my mate it wont have been serviced regularly. If it was the coil would this cause the lock out light to come on after two minutes of running. And then after 45 seconds the next time the boiler is tried? if the answer to this is no would that point to the copper filter. Cheers
These coil failures are particularly fickle really....sometimes they pack in completely, other times they pack in due to a temperature increase.
The only real way to test them installed is to use a magnet stick - if you put one of these against the coil it lights up if a magnetic field has been induced....well impressive!
I keep coils in stock - they cost around £30 give or take to buy, but come with a complete pump (around £65).
John :)

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