Worcester Junior pump change

[newcastleutd]

Hi

I need to change the pump inside my boiler, what is the best way?
should i drain down the boiler only or the whole system?
The boiler is in kitchen cupboard.
I have heard about just dropping the pressure but not sure that would be wise with a pump head change?

 

[grahamtheplumber]

most isolation valves on combis leak when turned off and then on again.drain the whole system down.

 

[holty]

second that, if its the old junior. the wb iso valves are the pants. if the pump valves are stubborn. just change the head with the 4 allan key bolts. probably easier anyway.