Can be join, but need to solder, not just twist and tape. And use 3M tape

This one you need neutral and live wires that connected to the water heater, doubt you can do it on the db box without tracing the neutral wires.

It can also be solar, remember solar also have storage heater.

Don't know the detail how it happen, could be wiring got bitten by rat, or leaking on the tank that shorted the wires. Many possibilities, hope the press share more details.

This post has been edited by weikee: Jul 27 2016, 04:55 PM

When the storage heater is not switch on for more than 1 day, it will need minimal 5mins to warm the water, will take longer if tank are bigger anything bigger thab 35L consider big. If using it daily, don't need to "wait" just switch on and you have hot water.

"wait" because between the storage tank and shower, the pipe is cold water.

What happen if drain at night? still need to switch on backup heater, and is even slower for solar backup heater to heat the water. BTW, Solar heater will not get hot water as hot as Storage (maybe micro solar will)

Unless the owner bath tub in the morning

Most likely (guessing) the storage heater is some "chap palang" brand. A good brand will have minimal 2 failsafe features inside.

And next is user need to practice switch off after use. This is passive safety.

For my house, i do a simple check, just switch on 30mins, if meter still running, is time to inspect. So far ok.. touch wood