Immersion heater problem

[user 33524]

So I’ve been having drama with my immersion heater for a while now. The tank has one element which is top fed entering the tank diagonally - no idea if this is a long or short element. I’m on economy 7 and my storage heaters work fine. I’m not getting any overnight water heated up so on a morning the water is cold. The trip button is constantly popping out but if I push that back in and turn the boost dial this will give me some hot water but it trips again frequently and quite quickly and I’m sometimes having to reset the button and turn the dial 3/4 times in the day (dread to think what this is doing to my electricity bills).

Has been checked for air locks and nothing has been picked up in that area and the thermostat has been replaced a little while ago also. 
 

any ideas would be greatly appreciated

 

[ProDave]

Start by replacing the thermostat.

In the longer term if this is your own house, think of replacing the tank for one with two immersion heaters both into the side of the cylinder.  Top mounted immersions are nothing but trouble.

 

[baldelectrician]

The immerser is probably kaput

If it is a top entry you can get a dual immerser with 2 elements (one long for night and one short for boost)

This saves you changing the cylinder

 

[kerching]

That's only the second person I have ever seen call it an immerser!

just saying