Ball valve sizes

[Andy R]

My house has been plumbed so that everything apart from the kitchen tap is fed by the tank in the loft (that's 3 loos, 3 basins, a bath and 2 showers). Consequently in the morning with everything being used the tank upstairs can run out of water. As a quick fix (before getting involved in major replumbing) I'd just like to get the tank to fill up quicker. The existing standard ball valve only allows a limited amount of water through it as it all appears to have to get through an approx 5mm hole. Is there a better valve available, ideally one which would allow the full capacity of the 15mm cold feed to fill the tank. I may also have to put a second tank alongside it and run them in parallel.

TIA

Andy R

[IMM]

Try a 3/4" ball valve. You will have to fit a 3/4" FBSP x 22mm fitting and have a 22mm x 15mm reducing compression set that fits inside the 22mm section of the fitting. This will ensure full flow and make sure the overflow is not undersized.

[Peter Taylor]

IMM wrote

Yes that's one way I suppose, but far simpler and cheaper to just use a 15mm full-flow lever-operated valve. It has the same ID as the pipe.

[IMM]

He is on about a ballcock and valve.

[Andy R]

Do you know what they're called or where to get them?

TIA

Andy R

[MrCheerful]

If you have a stopcock in the way then make sure it is fully open or replace with a "full-bore" ball valve, screwfix sell them. The ball valve in the tank may be restrictive, if so then replace with a Torbeck type valve assembly as these flow much faster. An alternative to an extra tank might be a larger tank or to put two ballvalves on the one tank.

MrCheerful

[Simon Avery]

Hello Andy

Oh yes. Agricultural suppliers have a wider than normal range of ballvalves, although you'll probably need several pipe adapters to get down to 15mm, since they're usually 1" or 3/4".

Another alternative is to T off the supply pipe and have a second normal ballvalve coming in. Probably the cheaper option, about a fiver for parts.

BUT, first thing in the morning water pressure drops rapidly because you're not the only one drawing it, so I'd personally go for the second tank in parrallel option. One or two 28mm pipes running between them ought to be adequate.

[Andy Hall]

Yep, I've done both of these in the past.

Adding an extra float valve, I found, could increase the filling rate by about 50% as long as there is adequate mains pressure and the pipework is also adequate in bore.. If not, it may not make a huge improvement.

Adding a second tank is certainly helpful but there are some caveats.

- Make very certain that the roof structure can take the added weight. Every litre of water adds a kilo - a typical 200 litre tank..... roll of drums... 200kg. The weight needs to be distributed and there needs to be adequate support as well - locating over a load bearing wall is common.

- The tanks should be piped together, and it's important to fill into one and extract from the other in order to maintain a flow and avoid stagnation in the second tank.

- Each tank should have a separate and adequate overflow.

.andy

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