The job brief was the oven was not working. But on arrival the domestic tenant says the RCD trips out when she puts a front ring on, so had stopped using it. So I throughly and gingerly check out the cooker fully but NFF. Then check the RCD and again NFF. Switch on the oven, rings etc and all is OK. I am about to leave and decide to check that RCD again and notice the voltage at the cooker panel socket is 220V, but the the ring socket is 240V! Front plates off and I find the double pole switch in the cooker switch unit is overheated and the cables are burnt for a couple of cm's back from the terminals. Probably a lose connection caused the overheating. I replaced the cooker switch, repaired the wiring and retested all OK. Now here is my question, could I still have a fault here that is causing the RCD to trip because I cannot fathom out why just an overheated cooker switch would cause an RCD trip? It was a few days ago now and I have not been called back, so it could be all OK.
By the way, don't you just hate domestic work. Each time the RCD tripped and was re instated the burglar alarm sounded and needed the tenant to put in the PIN code. I could not find the alarm isolator anywhere which made it a right pain. Then to make it worse on the final occasion I put the power back on the very loud CO2 alarm in the house decided to pack up and sound continuously. At first I thought it was the nearby smoke alarm making the din, but on unclipping that one I found that was disconnected inside! The CO2 alarm was completed shot anyway and would not reset, so had to replace it. Throughout this racket from alarms there was an infant in the house, and the CO2 alarm was in the infants room! Other things noticed was the the house had three CUs, one had the tails cut off and was disused, but the earthing conductor for the third CU was via the 2nd disused CU. Finally there was so much stuff in the cupboards that I could not find the water main bonding termination anywhere. The tenant was due to move out so i have recommended a periodic inspection when empty.
Just a normal day I guess
By the way, don't you just hate domestic work. Each time the RCD tripped and was re instated the burglar alarm sounded and needed the tenant to put in the PIN code. I could not find the alarm isolator anywhere which made it a right pain. Then to make it worse on the final occasion I put the power back on the very loud CO2 alarm in the house decided to pack up and sound continuously. At first I thought it was the nearby smoke alarm making the din, but on unclipping that one I found that was disconnected inside! The CO2 alarm was completed shot anyway and would not reset, so had to replace it. Throughout this racket from alarms there was an infant in the house, and the CO2 alarm was in the infants room! Other things noticed was the the house had three CUs, one had the tails cut off and was disused, but the earthing conductor for the third CU was via the 2nd disused CU. Finally there was so much stuff in the cupboards that I could not find the water main bonding termination anywhere. The tenant was due to move out so i have recommended a periodic inspection when empty.
Just a normal day I guess