Mystery of the hidden main water bonding.

[Mr Hehound]

Could I get your opinion on this please?

Went to have a look at adding a new circuit for outside power to a property.

Spare way on the rcd protected side of the consumer unit so a reasonable start.

Opened up utility boxes (on exterior wall of garage) and find 16mm main earth and 10mm gas bond run to consumer unit through garage wall. 100A service head fuse, 25mm tails and a handy 100A DP isolator are all fitted. Earthing is TNCS.

Asked homeowner where water comes into property which is under the sink. Comes up in plastic to brass stopcock, to copper then branches off via into copper and some plastic via some soldering and some JG speedfit fittings.

However, no sign of main water bond within 600mm of water inlet.

Open consumer unit and see that the 10mm gas bond is where it should be as is the main earth AND there is a 10mm bonding cable in place for water.

Tested the gas bond and main earth for continuity of main earth and gas bond and these are ok.

Went back under the sink and tested continuity between the end of the mystery water bond and the metal pipework and have continuity so it appears it is bonded somewhere - just not accesible or within 600mm of the incoming water.

What to do? Is this acceptable with a note to say water bond tested to pipework and shows 'x' ohms but is non-accessable or should a new bond be run (which could be done fairly easily in this case) where it is accessable and within regulation distance from incoming water?

 

[chrish_1977]

If its plastic coming into property, have you done insulation resistance between water and everything else, if not connection then you don't need to bond.

 

[Octopus]

If it comes in in plastic there is no need to bond

 

[telectrix]

probably bonded water to gas through the metalwork of the boiler anyway.

 

[MDJ]

Sounds like it is bonded, just do the Job and add a note saying continuity via a meter was confirmed but visual confirmation not confirmed and suggest via a recommendation further investigation is a needed, and that's that, if continuity was not confirmed then a different story, but you said you saw the cable in the distribution board and it tested out so stop worrying about it and get the Job done.

 

[Mr Hehound]

Thanks all. Your help is appreciated.

 

[Englishman]

Always been told to test continuity between the board and cold water feed of sink if I can't visually inspect stopcock bonding. Put it down in observations as a c3 and put the continuity figure, usually 0.00 ohm but I always put 0.01 ohms.