Berryterry as @LMSC has said that little lever behind the group will operate the pump. If you physically push it back so it opens the valve, does the pump run?
If it doesn’t then open up the electronics bay (side panel) and have a look at all the wiring, check there isn’t a loose wire from the 24 volt transformer. Then open up the control board, a few screws and check the connector to the 24 volt supply isn’t loose and all the connections from the pressurestat, (round black thing with red black and white wires coming from it (top of boiler bay) are OK. Have a peep at the glass fuses , Im sure they are all OK.
Of course have it unplugged whilst you do this.