Immersion heater tripping circuit breaker

Folks, a neighbour is having problems with his water heater tripping the circuit breaker it is on, each time it tries to switch on at night. The same breaker knocks out all his sockets as well, so he is constantly having to set up his VCR and other bits each day.
The "boost" heater works fine and causes no probs, so I am guessing that the main element is breaking down or wiring has gone astray maybe......any electricians out there who might be able to help?
Swapped over his controller with mine yesterday to remove that from the equation - his controller worked perfectly with my heater. Other than that it looks like two cables running from controller to two heater elements - one for main element and the other to the boost.
Your advice appreciated.

There is a pinhole leak in the immersion element and there is water getting into the wiring.
This is the most common issue when this fault occurs.

Solution: replace immersion element.

J

Jildy said:

There is a pinhole leak in the immersion element and there is water getting into the wiring.
This is the most common issue when this fault occurs.

Solution: replace immersion element.

J

Click to expand...

Yep, the insulation has broken down on the main element. As above replace element.

Is it an economy 7 controller? This is a night rate system and uses two seperate elements. The furthest element from the bottom of the tank is usually the boost.

Thanks for the responses folks. Swapped over wiring so that he now has night time heat like he used to (by using the boost element), but no boost for later in the day. It means the water is hot in the morning for the moment. Will source a new element and suss out costs of plumber to do the job. I think we will need a plumber as the system uses a pump to both fill the tank and send water to the taps, shower, etc. No clue about that type of system.

redtaz said:

Thanks for the responses folks. Swapped over wiring so that he now has night time heat like he used to (by using the boost element), but no boost for later in the day. It means the water is hot in the morning for the moment. Will source a new element and suss out costs of plumber to do the job. I think we will need a plumber as the system uses a pump to both fill the tank and send water to the taps, shower, etc. No clue about that type of system.

Click to expand...

Plumber is your best bet, he could probably pick up an element cheaper than you too..