I think I'll check for an active-earth breakdown just in case a motor has a faulty winding. I'll try and dig a little deeper on the weekend. I recall in the past there was a noisy-bearing type noise in this unit, so maybe the other motor has seized up during the period of inactivity? The visible motor turns very smoothly, but I'm aware that there is a second motor in these systems. Maybe the system somehow remembered the 'on' from the networker? I think that may have been a motor start-up noise just before the bang. However, when I switched the underfloor unit off and back on (via the power point and after swapping the outlet), the second time it did make a noise. I did hit the power button on the networker but it didn't seem to make any difference. When I went inside to check the 'networker' it was still completely blank (no time, no soft key menus).

The first time I switched it on, nothing happened at all (which is normal). The motor rotates very freely so I'm not convinced it is the motor.ДЄlso, I didn't realise it at the time, but the circuit breaker tripped too.Дoes anyone have any ideas or pointers as to what might be wrong? I'll probably have to wait until the weekend before I have time to look further.ДЄny advice and guidance would be much appreciated.ДЄs far as what 'blew', its not likely to be the motor as it would not have energized the motor as yet, it only does that when it is turned 'on'. The nearest I can tell, is that the flash may have been near the blower motor. I turned everything off and removed the cover to look for any obvious problems. It went BANG! and there was a flash near the right-hand side vent (the one nearest the 'star' sticker). When I plugged it in to the other outlet and switched on - something unexpected happened. It was on, so I thought I'd try the other outlet (its a double outlet) just in case. I figured that maybe I plugged it in but had forgot to switch it on? I went under the house again to check. However, when I checked the controller inside, the screen was still blank. At first, nothing happened when I plugged it in (and I didn't expect anything to happen). The central heating unit has been left unplugged for several months now, but I thought I should plug it in in preparation for when it is next needed. In the process, the power outlet to the central heater (fitted by the heating installer) was wired with the active and neutral transposed.

The tripping fault was eventually found to be a rodent chewed cable. I left the central heating unit unplugged, but the tripping remained. All of them checked out okay except for the central heating unit that showed a little bit of leakage. I initially suspected that I had a faulty appliance so I did an insulation breakdown test on all the appliances. Does anyone have any experience with repairing a Brivis central heating unit?ДЄ while back I had trouble with a electrical circuit intermittently tripping the circuit breaker.

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