Has the ACB has had it? :-(

Hi,
Hopefully someone on here may be able to help me. I'm trying to help a friend get his BM2000 working. The 32a BS88 fuse blew, melting the carrier, I've replaced both of the fuses with new RCD's, and the 5a 'quick blow' fuse which had blown, in the ACB (I think its a GT155 board by the way) I got the power back on giving me hot water, but no heating. I got the red display saying 'on' and 1 of the 3 little green leds lit up I'm guessing I should have all three?? And the green led for 'normal operation' is on too.
I've changed the Omron G7L-2A-T 200-240VAC relay too more in hope than expectation, but nothing? I've got no power at any of the 3 pumps or at the terminals on the switch heating element. So, I'm thinking that the ACB may have blown? I had a look at next doors and they've got all the green leds on and power at the pumps. Looking on the back of the ACB there is some slight black burn marks on a couple of the solered terminals which makes me think its the ACB. What do you think??

Any help appreciated. I'm a sparky, so I feel confident about changing it myself, but I've heard 'jumpers' being mentioned and if that could be explained to me it'd really help.

Has this BM 2000 got the "switch" option?
Have you the manual on the unit?
Mike
MGC/H2O
Norfolk

Hi Mike,
Please excuse my ignorance, I'm not sure what the 'switch' option is. How would I know? I do have the manuals, but I'm at home now and notwhere the BM2000 is.
Cheers for replying.
Si

I would think you have the switch option.
It is an electric back up.
You need to look at the books a bit more.
Check the switch knob is in the right place for boiler.
BUT
It does look like the main PCB has gone.
Check a bit more to try and see what took the board out.
Mike
MGC/H2O
Norfolk

Mike,
I've emailed you a picture of what I see when I take the front panal off. Hope you don't mind.
It does have 3 positions for the silver knob by the clock, 'normal operation', 'emergency heating' and 'emergency hot water' or at least I think thats what they say? I will sit and study the books more tomorrow. When you say 'try and see what took the board out' What sort of things am I looking for. The first thing I was faced with was a nuked fuse inside the carrier. Is it possible that it blew with such force that that's what has blown the PCB?? I'm just a humble sparky and anything past the PCB is a little bit out of my league tbh.
Si

I've got to go pick the daughter up, back soon. Thanks