Storage tank in loft not filling

[Steverb22]

We have had a halt in our water supply from the plant. Our water has now been turned back on but our cold water storage tank in the loft now has no water coming in despite having water downstairs direct from the mains. Any ideas??

 

[Old Salt]

Ball float valve could be stuck, give it a gentle tap and see if it will allow water to pass.
Try moving the small white plunger on the end of the valve manually. If water starts to flow check that it shuts off once the ball float rises.

 

[Steverb22]

Ball float moves up and down freely. Moved little plastic valve and nothing

 

[Steverb22]

I’m thinking there must be an airlock as water was off for two days. Yes, we were caught p in the Hampshire failure this week. Southern water are saying internal so not their problem but was fine before they turned the water off!

 

[HERTS P&D]

The washer needs replacing.

Andy

 

[Old Salt]

So you turn the water off and strip down the valve, give it a clean, check or change the washer and reassemble. Whatever you do don't leave it like that in case the valve frees up but wont shut off again.

I don't think it will be an airlock, more likely the valve is just stuck or the washer is stuck to the face of the valve.

 

[JohnD]

You may find it quicker and easier to swap the valve for a new one, while working in a cramped and dark loft.

If you wish, you can later dismantle, clean and rewasher the old one at your leisure on the kitchen table, where any shall parts or tools you drop are easily retrieved. You can then put it in a plastic bag and hang it next to the loft tank ready for next time.

 

[terryplumb]

The float valve is blocked. Just replace it.

 

[JohnD]

BTW if there is sediment or grit in the pipes (likely) it is a good idea to run the pipe, open without the valve, into the tank briefly so water gushes out and washes away loose particles.