pump speed query

This pulsacoil has a British gas 3sp grunny fitted and it has been wired with L bypassing the speed controller, what is the sequence of the controller from switch on/cold?

I will replace the pump but I would like to know if this was done because a) wrong pump b) faulty controller c) all of the above

Also any thoughts on both rod stats overheated, look pretty new and the contacts appear to work normally.

Wrong pump.
Fit the correct one and see how you go.
What rods stats have you?
Mike
MGC/H2O
Norfolk

rod stats look kosher, elements appear to be pulsacoil specified from electric water heating ltd.

im assuming the bottom one is boiling out, tripping both stats eventually, I cant believe what the other engineer has done with the pump, the water coming out of the taps is far far too hot.

Are the rod stats sealed?

yeah, sealed at 73 degree's

Could be a lot of sludge or scale making the bottom one over heat.
Has your unit got a relay?

Yes it does

Check the relay has not stuck or jammed on.
Mike

Grundfos 15-50X18 is the correct modulating pump. Also one of the stats maybe failing.