Unvented cylinder drain - help

[msdmjb]

Yo, first post so please be gentle !!

The anti corrosion Protech system on my unvented Ariston hot water cylinder has broke requiring me to drain some water out the tank to replace it. I have the part, have a hose attached to the drain of the tank and just want some feel good factor before doing anything !! My intention is to turn off the mains, open the hot taps to allow some water out then open the drain valve and hopefully take about 1/3 of the tank of water out, undo the broke bit from the side of the tank, fit the new bit, close the drain valve and then open the mains. At this point I assume that having the pipes open will push any air out preventing any air locks.

Anybody like to comment, apart from getting a plumber in !!

Thanks

 

[chrishutt]

Sounds OK to me.

 

[Paul Barker]

I'm sure you are not this stupid, but just checking in case, some unvented's have a commissioning cock half way up, can be a drain off but isn't the one.

If it's an internal expansion (bubble top) you get better bubble formation when you hold commissioning cock open while you refill it until water comes out of it.