Boiler not firing when shower switched on

[greatvalley]

Somebody please help!!

I have just had a new Worcester 28i junior installed and now my thermostatic shower doesn't get hot? The shower was about six years old so I thought maybe it was past it and couldn't handle the new boiler so I have replaced it with a new thermostatic shower. Now this doesn't get hot either.

I have noticed that when I turn the shower on the boiler isn't lighting up which is obviously the reason there is no hot water, but it lights up and provides hot water when the taps are turned on? It is as though the boiler isn't recognising the drop in pressure and switching on.

Why is this happening? New boiler, new shower, what could it be?

 

[TicklyT]

Blocked hot feed to shower?
Reversed H & C feeds to thermostatic shower?

 

[greatvalley]

Wahhaaaayyy!!!!

I think I have sorted it. It seems to work when the economy mode button on the boiler is switched on. I don't know why but it seems to work.

Fingers crossed it stays ok.