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Currently doing a kitchen refurbishment. When doing the quote, peering under the kitchen sink, noticed bonding to water was 4mm, and same for gas. Property has a TNC-S supply, and had replacement CU in 2010 (no certs available). Said to customer bonding should be upgraded to 10mm. Easy cable route, which customer decided to run himself (ex electrician) and I will connect & test, jobs a goodun.
So I turn up before kitchen fitters to do my first fix. The customer has done good job of running bonding cables and has removed old kitchen floor units around incoming water pipe, to reveal it's plastic. Now next bit is not my point (so lets not debate that!), no probs cable not wasted, connecting to household copper service, will comply with reg. 528.3.4.
Connect and test gas & water bonding. Gas fine but water giving reading of 19 odd ohms. Further removal of old kitchen units expose section of plastic push fit, between kitchen copper pipe and adjacent downstairs toilet copper. Starting to think its a pointless task, customer is adamant the rest of the house cold main etc, is in copper as he had refurbished said downstairs toilet.
Now for some reason, I decided to test Extraneous Conductive Parts in the bathroom. A piece of copper to toilet, copper tails to flexi-hoses to basin and metal radiator with copper tails. Reading I obtained on tails, using my MFT IR test, was 0.01Mohms (tests carried locally be between circuit cpc and ECP's). Bathroom has electric shower (on RCD) and light (on MCB only).
Now from reg 415.2.2 and the helpful vid by Chris Kitcher, I understand (lets keep it simple with the shower), any reading below 1667ohms doesn't need bonding, above 1667 & below 0.02Mohms does, and above 0.02Mohms is just a piece of metal (metal rad was >532Mohms).
My question is, is the above paragraph correct, and if so, what would you advise the customer on the bonding of the extraneous conductive parts, i.e. the copper tails?
The copper tails are no more than 300mm long. I'm kinda erring on the side of ignoring them! Bathroom was refurbished 2 years ago, walls & floors tiled. All downstairs CH pipes give very low readings, as do the pipes entering ceiling below bathroom, so guess push fit used in bathroom refurb'.
So I turn up before kitchen fitters to do my first fix. The customer has done good job of running bonding cables and has removed old kitchen floor units around incoming water pipe, to reveal it's plastic. Now next bit is not my point (so lets not debate that!), no probs cable not wasted, connecting to household copper service, will comply with reg. 528.3.4.
Connect and test gas & water bonding. Gas fine but water giving reading of 19 odd ohms. Further removal of old kitchen units expose section of plastic push fit, between kitchen copper pipe and adjacent downstairs toilet copper. Starting to think its a pointless task, customer is adamant the rest of the house cold main etc, is in copper as he had refurbished said downstairs toilet.
Now for some reason, I decided to test Extraneous Conductive Parts in the bathroom. A piece of copper to toilet, copper tails to flexi-hoses to basin and metal radiator with copper tails. Reading I obtained on tails, using my MFT IR test, was 0.01Mohms (tests carried locally be between circuit cpc and ECP's). Bathroom has electric shower (on RCD) and light (on MCB only).
Now from reg 415.2.2 and the helpful vid by Chris Kitcher, I understand (lets keep it simple with the shower), any reading below 1667ohms doesn't need bonding, above 1667 & below 0.02Mohms does, and above 0.02Mohms is just a piece of metal (metal rad was >532Mohms).
My question is, is the above paragraph correct, and if so, what would you advise the customer on the bonding of the extraneous conductive parts, i.e. the copper tails?
The copper tails are no more than 300mm long. I'm kinda erring on the side of ignoring them! Bathroom was refurbished 2 years ago, walls & floors tiled. All downstairs CH pipes give very low readings, as do the pipes entering ceiling below bathroom, so guess push fit used in bathroom refurb'.