I have a Buderus Logamatic 4211 with an FM442 unit. Before going to bed in the evening I check that everything is OK. I check again in the morning and recently I am greeted with a red light on the FM442 unit which controls Circuits 3&4. I see no error message on the MEC2 Programming unit. The Manual says: “General fault. e.g. on-site faults, external faults, wiring faults, internal module faults, manual mode. The fault messages appear as plain text on the MEC2 programming unit.” I wish they did! Any ideas anyone?