I unfortunately made the error of employing an electrical contractor (NICEIC approved contractor) for a partial rewire, new consumer unit and substantial upgrade of my house electrics, who has not only tried just about all the usual sharp practice tricks (putting in cheaper specification than specified eg split RCD when RBBOs were specified, not doing certain parts of the work, claiming to have done work that he hasn't, upping the price by 40%, withholding the completion certificate etc etc) but also on closer inspection has not put in what I would have normally expected.
The new radial circuit to the utility wing (utility room and small workshop), serving boiler, washing machine, freezer plus an additonal double socket and two singles has been fitted with a B16 MCB. I would have expected a B20 for this. Are there any good reasons for using this lower MCB?
I've also had two different stories off the contractor so far as to what the original circuit wiring to the main house was, and what they now are. The lad on site assumed at first there were 2 ring circuits, given the fuse wiring and that there were two wires into the fuse board for each circuit. Then for some reason decided that there were instead two radial circuits to each circuit, ie from each fuse 2 radial circuits. I'm not sure if this was because he checked continuity and there wasn't. However I've checked the circuit layout (as the original wiring has been retained, and only very minor additions made which were all in new colour wiring, so it is quite clear what is new and what is old). The original was clearly a ring main at first floor with spurs to the ground floor (pretty standard as the house has solid ground floors) - I lifted the floorboards, carefully and systematically traced the line of the circuits and checked each socket and junction box. It would seem to me that if there is a discontinuity it will be through either a loose connection in one of the junction boxes or sockets, or that there is a damaged wire.
When the contractor was finishing the work I overheard him saying that those circuits were radial circuits, so I asked him directly and he said yes he had retained them as radial circuits which were fine for that situation. (Each circuit covers 40m2, incidently). On the new consumer unit we still have 2 wires (the original ones) to each of the two MCBs, which have been fitted with a B20 MCB. He hasn't altered the existing general circuit layout. Interestingly he is now claiming that the circuits are ring circuits, and he had to do a lot of work to make them into ring circuits, hence the £1500 extra on the price! One of the circuits had no wiring alterations, just two single sockets changed to doubles. The other circuit had three new sockets added all in one room so there is a small bit of new wiring in one room. The spurs are all still spurs.
I guess my question on this is, is it ever correct to fit a B20 MCB to a domestic ring circuit?
By the way I've had a word with NICEIC about the completion certificate and know the score on that, and will be taking action. It also turns out he has a reputation for upping the price very substantially, putting in cheaper than specification fittings, not doing work that he was meant to do, but charging for it, and also witholding compliance certificates and saying that they are not needed when very clearly the work comes under part P.
Sorry for the long winded post. I'd be grateful for clarification on the MCB ratings. Thanks.
The new radial circuit to the utility wing (utility room and small workshop), serving boiler, washing machine, freezer plus an additonal double socket and two singles has been fitted with a B16 MCB. I would have expected a B20 for this. Are there any good reasons for using this lower MCB?
I've also had two different stories off the contractor so far as to what the original circuit wiring to the main house was, and what they now are. The lad on site assumed at first there were 2 ring circuits, given the fuse wiring and that there were two wires into the fuse board for each circuit. Then for some reason decided that there were instead two radial circuits to each circuit, ie from each fuse 2 radial circuits. I'm not sure if this was because he checked continuity and there wasn't. However I've checked the circuit layout (as the original wiring has been retained, and only very minor additions made which were all in new colour wiring, so it is quite clear what is new and what is old). The original was clearly a ring main at first floor with spurs to the ground floor (pretty standard as the house has solid ground floors) - I lifted the floorboards, carefully and systematically traced the line of the circuits and checked each socket and junction box. It would seem to me that if there is a discontinuity it will be through either a loose connection in one of the junction boxes or sockets, or that there is a damaged wire.
When the contractor was finishing the work I overheard him saying that those circuits were radial circuits, so I asked him directly and he said yes he had retained them as radial circuits which were fine for that situation. (Each circuit covers 40m2, incidently). On the new consumer unit we still have 2 wires (the original ones) to each of the two MCBs, which have been fitted with a B20 MCB. He hasn't altered the existing general circuit layout. Interestingly he is now claiming that the circuits are ring circuits, and he had to do a lot of work to make them into ring circuits, hence the £1500 extra on the price! One of the circuits had no wiring alterations, just two single sockets changed to doubles. The other circuit had three new sockets added all in one room so there is a small bit of new wiring in one room. The spurs are all still spurs.
I guess my question on this is, is it ever correct to fit a B20 MCB to a domestic ring circuit?
By the way I've had a word with NICEIC about the completion certificate and know the score on that, and will be taking action. It also turns out he has a reputation for upping the price very substantially, putting in cheaper than specification fittings, not doing work that he was meant to do, but charging for it, and also witholding compliance certificates and saying that they are not needed when very clearly the work comes under part P.
Sorry for the long winded post. I'd be grateful for clarification on the MCB ratings. Thanks.
