back boiler and rad advice please

[gwa70]

i need to change a valve on my bathroom rad......i have a back boiler and cloed tank in the loft.....how do i isolate the water supply so i don,t get water everywhere when i take the old valve off........i,ve only ever done this with combi boilers ..does the whole system need draining or can is there a valve somewhere i can cloe then drain the water in the pipes off through a tap etc....
thanks.....

 

[Ivor Bates]

Drayton bungs or freeze it, other than that drain it!

 

[gwa70]

i,ve not used either before.....any opinions on which is easier and works best......

 

[Ivor Bates]

Draining always works better as it avoids any mishaps. And also helps the rest of us, by keeping our insurance policy's lower, should there be one:wink:

 

[gwa70]

the only drain valve i can find including the rads is on the tank itself and i can,t get it open......i have however found 2 taps on the pipes in the cupboard under the tank........i assume one is cold water inlest and the other hot water out..........having closed both of these am i right to assume i don,t need to drain the tank and can simply open the hot water tap in kitchen and bathroom to drain off whatever is left in the pipes........have turned off back boiler and knocekd electric off to tank etc............

 

[GQuigley67]

you have to drain the heating system, there should be a drain valve outside, if there isnt then your better looking at freezing, you dont want to be getting any airlocks

 

[villa_tom]

If you dont have a drain off then whip the rad of the wall and drain from the rad valve itself. I have done this a few times and often find it drains quicker. Plus if its an upstairs rad it will only drain upstairs.

Or if your feeling brave you could snatch it