Christian McArdle wrote:

6. Wet heating element*.

Christian.

* This happens when a mineral insulated heating element has absorbed water.
This leads to earth leakage that can trip an RCD. It can be cured by warming
the element to expel the water. This can be done (after eliminating all
other causes and taking extra precautions) by bypassing the RCD and letting
the heating element run for many minutes. Then the RCD can be reinstated.


There are some problems with doing this.

1. Earth leakage will occur, and in some TT systems with only the RCD
as protection, this is somewhat dangerous. Not only may it make the
shower water live, but may make everything earthed in the house live.

2. Heating the wet insulation will boil the water off, but as it cools
it will simply suck water in again. Realise that the seal is gone, this
is why its wet.

You can run immersion heaters quite happily on leaking elements, but
not showers. If you have a leaking element on a shower, replace it.


NT