Good morning.

I have a client who is in the process of selling his house and I did a compliance certificate for the property. All my tests and readings obtained is normal and the earth continuity throughout the property is 0.1Ω max. The bonding is also displaying 0.00Ω on my Insulation Resistance tester. All the water pipes have been properly bonded and connected to the main earth terminal. Since replacing his geyser a few months ago, he has reported to me that he feels "shocking"/"electrical tingling" sensations whenever he is in the shower and he touches the taps. My team and I have been back to his house now on a number of occasions and I cannot detect any potential difference between the water pipes (hot and cold) and earth. We have installed additional earth continuity conductors and I have even bonded the cold water and hot water pipes at the point where it enters through the wall into the bathroom and ran an earth continuity conductor from the Supply authority's earth terminal at the kWH meter box which is about 1m away to these pipes.

He reports that everything seems to be normal for a few days and then suddenly for a day or two he experiences this issue. He contacted me yesterday and told me that he feels the shocks underneath his right foot when he touches the taps, whilst in the shower.

When I did my tetsts, I obtained an Earth Loop Impedance reading of 0.57Ω, Voltage between Neutral and Earth at the point of supply is 0.726V and as I previously said, I get 0Ω earth continuity readings between the earth terminal in the DB as well as the meter box's supply earth terminal. The geyser is connected through earth leakage and it should trip if leakage currents do occur. I tested the earth leakage, which I replaced about 3 years ago and it works fine, tripping at 30mA. As I said, it is a brand new geyser and element (less than 6 months old). According to him this issue started after he had the geyser replaced, Before we did the certificate of compliance. He also said to me that he had the plumber back there a number of times to check the plumbing before he contacted me.

I did notice that his water supply is polycop up to the point where it comes out of the ground against the house and then it connects into copper pipes. He told me that he has been in the house for over 20 years now and it is the first time that he experiences this problem.

Has anyone on this forum ever come across a problem like this? As I said, we've been back to his house on a number of occasions now and cannot find anything out of the ordinary.