grundfos selectric 4 pump question

[shd1970]

Hi all,

I have a grundfos selectric 4 pump and have cleaner in my central heating system at present which i now need to drain.

I am being advised that i need to drain as much as possible and then refill with clean water and run "just the pump" for 20 mins, and then drain and repeat 4 or so times to dilute the contents as i have drop feed radiators that i cannot drain fully.

Can anyone tell me if its possible to run the grundfos selectric 4 without turning the central heating on as i dont seem to be able to.
I have removed the bleed screw to check and the spindle only spins up when the boiler is turned on.

Can anyone confirm please ?

 

[cozzmic]

Just turn off the boiler thermostat so the pump runs without the boiler firing

 

[shd1970]

Thanks for the reply cozzmic.

Sorry, i should have explained that my boiler is an old Concord WRS255 which only has a temperature wheel to select a temp of 1-6.

Also, it has an old Randall 103 timer so it can only be set to be on constantly or on the timer.

Is there any other info that i can provide that will help ?

thanks again

 

[cozzmic]

Turn off the gas isolation valve at the boiler, turn off the pilot or shut off your gas at the meter. Remember to relight the pilot when you have finished.

 

[shd1970]

thanks for the input cozzmic

pretty logical come to think of it - should've thought if it myself

thanks again