Worcester Greenstar Heatslave 18/25 lockout light on

28 Nov 2014
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United Kingdom
Hi everyone. Last week I ran out of oil and I noticed the lockout light is on on the boiler. Ordered new oil which came 3 days later,but in the meantime I have turned off the boiler and the water pressure went down to 0. So, I tried to restart the boiler but no luck.After reading some advice on here , i have topped the water to 1.5 bar, bled the oil pump until the oil came out,tried to reset about 50 times but the thing still won't start.

I have a Worcester Greenstar Heatslave 18/25 installed about a year and a half ago.When i try to start does a noise for about 20 seconds then i can hear 2 clicks,then it stops and the lockout light comes on again. When you turn the hot tap on it clicks as well but no ignition. The thermostat was around 25 degrees, the knobs for HW and CH at 3 and the HW was OFF and the CH was ON.
I have made a video and posted it on youtube.Here is the link

Any help appreciated.

Thank you

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Hi there, I was googling my Worcester boiler and the image in your thread matches exactly what my boiler looks like. Last weekend the boiler was working fine and I left the thermostat set to 14 so it would come on during the week (I work away during the week). Got home this weekend and noticed house was a bit cold and saw that the lockout light was on on the boiler. It was serviced about a year ago, but the system has barely been used. Anyway, two things happened this week which might have caused this - I always turn off the water at the stopcock, and the cleaner was in and probably ran the hot tap to clean the bathroom. Also had the tank topped up with oil as the whole famlee are coming for Christmas. I don't even know how to try and reset the boiler, because the lockout light is just a light and not a button. I only moved in in March, so I'm still learning the house. Did you get your problem fixed in the end, and do you know how I can just 'reset' the lockout to see if that fixes it? Thanks
Think the reset button is behind the front panel ,below the two dials( for hot water and central heating temperatures). Long time since I have seen one of these boilers ,can you take a pic and post here , from below looking up. Think there are two reset buttons in that area and the one you want is on the left.
Lift the top case panel and you will see the reset button lit up on the control box. Press it and let go.
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May need to bleed pump bit more but if ran out of oil be prepared to change oil pump it may be
goosed ( a festive answer)Bob
Thanks everyone. I found the reset button, and the boiler started and the heating came on so good news there. Because it had been switched off completely I then decided to set the clock and the programmer to get the heating on the timer. Set the clock ok, set the programme for mornings and evenings ok too. Then pushing through the button it went clock? prog? test? hol/day? I just pushed on through the last two, but alas, now I can't get it to come back on. All the lights are on, the time is in the middle of the 'timed' time, so should be on, and nothing. So I've been googling for the programmer instructions and just can't find them, although I've found the manuals for just about everything else.. Please can someone help again?
Hi, I know it's an old thread but I have a similar problem with my boiler. Had to take off a radiator yesterday and the pressure in my boiler decreased to 0 bars. I managed to repressurize it today, it's on 1,5 bar now but my boiler won't start. I bleed the oil pump also and there is no change, the thing will not start. Btw, lockout light is not on. I tried to reset it, still no change. What could be the problem?
Reset as per the instructions. Read the fault finding codes and remedies in the manufacturers instructions.

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