i have a potterton combi 80 and the central heating will not keep firing up it fires up at the beginning for about 30 seconds then switches off and will not fire again
could be a dry joint on the modulator board. there may be black sooty marks around the faulty area. take board off and look for black marks,signs of arcing on the board or burnt out printed circuits. just had this happen to me (2 dry joints)
