Worcester Bosch 30si no hot water

[Malikse]

can some one pls pls help me with my worcester bosch 30si has no hot water demand and fault code showing Blue light slow flash normally off flashes on and reset button flashing, (lock out) i can here the fan and sound trying to light up but dose not continue,, when i reset the boiler it will reset but will just go back to same problem again. i turn it off for about an 2 hour then turn ON the boiler it will work with hot water but not to hot even you put it on maximum heat for about an hour fan working green pilot light showing flame is on is working and it will work for 40 minutes, then problem will happen again and it wont start until the boiler will rest
PLS HELP ME
i read a post that they change the HEAT Sensor but doesn't now exactly
is this the DHW temperature sensor pls help me
syphone is clean and no block to pipe

 

[Agile]

We don't like text speak here.

We give our time free to help and like to be able to read something easily!

 

[Malikse]

We don't like text speak here.

We give our time free to help and like to be able to read something easily!

I apologise Agile, can you pls advice me where to start I really need help sorry again if I upset some one