Boilermate runs continually after initial problem solved

Hi.
I have a boilermate a class and a gledhill boiler. I have absolutely no problem with heating or hot water - there is plenty of hot water and testing the heating it all works fine.
The problem I had was that the boiler would come on and fire for 30 seconds, go off and then come back on 3 minutes later and fire for 30 seconds, and so on.
The British Gas engineer came to service the boiler - all fine. He called gledhill who talked him through testing the boilermate. The pump was set to 2 but that has now been changed to 3. All the temperature readings for the water etc were apparently fine. So engineer leaves. And indeed the boiler no longer comes on and goes off.
Instead the pump comes on and stays on, permanently. The boiler is showing as active, and it's pump is on too, but I can hear it's not firing.
I have tried switching on the switch - the boilermate then makes a sound like the kettle boiling for a couple of minutes and then the pump switches off.
If I then switch the switch back off, everything is fine - for about 6 hours and then the pump in the boiler mate comes back on and stays on.
Can you please help with identifying the problem before I call British Gas back out?
The gas bill for my 1 bed flat is the same as for my parents 3 bed house at the moment!
Thanks in advance
David

Try switching the BM A off.
Wait then try it.
It does sound like the BM A main board.
But has the Gledhill boiler you have.
Got pump over run?
Mike

Thank you for your reply! If I switch it off, wait a bit and switch it on again it's fine for about 6 hours - it'll stop the pump running overnight but it's back on in the morning.
I don't know what pump over run is I'm afraid and the person I bought the house from threw all the instructions away instead of passing them on - the boiler is a gb15.
Thanks again
David

Go on Gledhill website and download the books etc for free!
Mike

Thank you I have done that but it doesn't mention the problem. How do I know if the boiler has pump overrun? David

Yes it does have pump overrun! According to the instructions that is one of the possible indicators on the boiler display. I have never seen that combination of lights though. When the pump on the boiler mate is running the boiler lights are in the "on with heat demand" rather than "no heat demand and over run on"


Thanks again, David

If the pump over run is carried out by the Gledhill boiler then the fault could be with that.
Or if not the BM 2000.
Mike

For anyone who comes across this post - an update!
The system seems to have settled down so I guess the BGas engineer changing the pump setting did the trick. It still requires an occaisional restart when the system (pump in boilermate) sticks on, but seem to have less trouble at the moment (touch wood).